diff --git a/Octokit.Tests/Clients/MiscellaneousClientTests.cs b/Octokit.Tests/Clients/MiscellaneousClientTests.cs
index ba998b2b..c9d8045e 100644
--- a/Octokit.Tests/Clients/MiscellaneousClientTests.cs
+++ b/Octokit.Tests/Clients/MiscellaneousClientTests.cs
@@ -14,11 +14,8 @@ namespace Octokit.Tests.Clients
             [Fact]
             public async Task RequestsTheEmojiEndpoint()
             {
-                var links = new Dictionary<string, Uri>();
-                var scopes = new List<string>();
                 IApiResponse<string> response = new ApiResponse<string>(new Response
                 {
-                    ApiInfo = new ApiInfo(links, scopes, scopes, "", new RateLimit(new Dictionary<string, string>())),
                     Body = "<strong>Test</strong>"
                 }, "<strong>Test</strong>");
                 var connection = Substitute.For<IConnection>();
@@ -42,18 +39,15 @@ namespace Octokit.Tests.Clients
             [Fact]
             public async Task RequestsTheEmojiEndpoint()
             {
-                var links = new Dictionary<string, Uri>();
-                var scopes = new List<string>();
                 IApiResponse<Dictionary<string, string>> response = new ApiResponse<Dictionary<string, string>>
-                    (new Response
-                    {
-                        ApiInfo = new ApiInfo(links, scopes, scopes, "", new RateLimit(new Dictionary<string, string>()))
-                    },
+                (
+                    new Response(),
                     new Dictionary<string, string>
                     {
                         { "foo", "http://example.com/foo.gif" },
                         { "bar", "http://example.com/bar.gif" }
-                    });
+                    }
+                );
                 var connection = Substitute.For<IConnection>();
                 connection.Get<Dictionary<string, string>>(Args.Uri, null, null).Returns(Task.FromResult(response));
                 var client = new MiscellaneousClient(connection);
diff --git a/Octokit.Tests/Exceptions/RateLimitExceededExceptionTests.cs b/Octokit.Tests/Exceptions/RateLimitExceededExceptionTests.cs
index d8995038..2505e231 100644
--- a/Octokit.Tests/Exceptions/RateLimitExceededExceptionTests.cs
+++ b/Octokit.Tests/Exceptions/RateLimitExceededExceptionTests.cs
@@ -16,11 +16,14 @@ namespace Octokit.Tests.Exceptions
             [Fact]
             public void ParsesRateLimitsFromHeaders()
             {
-                var response = new Response { StatusCode = HttpStatusCode.Forbidden };
-                response.Headers.Add("X-RateLimit-Limit", "100");
-                response.Headers.Add("X-RateLimit-Remaining", "42");
-                response.Headers.Add("X-RateLimit-Reset", "1372700873");
-                response.ApiInfo = CreateApiInfo(response);
+                var headers = new Dictionary<string, string>
+                {
+                    {"X-RateLimit-Limit", "100"},
+                    {"X-RateLimit-Remaining", "42"},
+                    {"X-RateLimit-Reset", "1372700873"}
+                };
+                var response = new Response(headers) { StatusCode = HttpStatusCode.Forbidden };
+
                 var exception = new RateLimitExceededException(response);
 
                 Assert.Equal(HttpStatusCode.Forbidden, exception.StatusCode);
@@ -30,7 +33,6 @@ namespace Octokit.Tests.Exceptions
                     "Mon 01 Jul 2013 5:47:53 PM -00:00",
                     "ddd dd MMM yyyy h:mm:ss tt zzz",
                     CultureInfo.InvariantCulture);
-                
                 Assert.Equal("API Rate Limit exceeded", exception.Message);
                 Assert.Equal(expectedReset, exception.Reset);
             }
@@ -38,11 +40,14 @@ namespace Octokit.Tests.Exceptions
             [Fact]
             public void HandlesInvalidHeaderValues()
             {
-                var response = new Response { StatusCode = HttpStatusCode.Forbidden };
-                response.Headers.Add("X-RateLimit-Limit", "XXX");
-                response.Headers.Add("X-RateLimit-Remaining", "XXXX");
-                response.Headers.Add("X-RateLimit-Reset", "XXXX");
-                response.ApiInfo = CreateApiInfo(response);
+                var headers = new Dictionary<string, string>
+                {
+                    {"X-RateLimit-Limit", "XXX"},
+                    {"X-RateLimit-Remaining", "XXXX"},
+                    {"X-RateLimit-Reset", "XXXX"}
+                };
+                var response = new Response(headers) { StatusCode = HttpStatusCode.Forbidden };
+                
                 var exception = new RateLimitExceededException(response);
 
                 Assert.Equal(HttpStatusCode.Forbidden, exception.StatusCode);
@@ -58,11 +63,10 @@ namespace Octokit.Tests.Exceptions
             [Fact]
             public void HandlesMissingHeaderValues()
             {
-                var response = new Response
+                var response = new Response(new Dictionary<string, string>())
                 {
                     StatusCode = HttpStatusCode.Forbidden
                 };
-                response.ApiInfo = CreateApiInfo(response);
                 var exception = new RateLimitExceededException(response);
 
                 Assert.Equal(HttpStatusCode.Forbidden, exception.StatusCode);
@@ -79,11 +83,12 @@ namespace Octokit.Tests.Exceptions
             [Fact]
             public void CanPopulateObjectFromSerializedData()
             {
-                var response = new Response { StatusCode = HttpStatusCode.Forbidden };
-                response.Headers.Add("X-RateLimit-Limit", "100");
-                response.Headers.Add("X-RateLimit-Remaining", "42");
-                response.Headers.Add("X-RateLimit-Reset", "1372700873");
-                response.ApiInfo = CreateApiInfo(response);
+                var headers = new Dictionary<string, string>{
+                    {"X-RateLimit-Limit", "100"},
+                    {"X-RateLimit-Remaining", "42"},
+                    {"X-RateLimit-Reset", "1372700873"}
+                };
+                var response = new Response(headers) { StatusCode = HttpStatusCode.Forbidden };
 
                 var exception = new RateLimitExceededException(response);
 
@@ -106,10 +111,5 @@ namespace Octokit.Tests.Exceptions
             }
 #endif
         }
-
-        static ApiInfo CreateApiInfo(IResponse response)
-        {
-            return new ApiInfo(new Dictionary<string, Uri>(), new List<string>(), new List<string>(), "etag", new RateLimit(response.Headers) );
-        }
     }
 }
diff --git a/Octokit.Tests/Http/ApiConnectionTests.cs b/Octokit.Tests/Http/ApiConnectionTests.cs
index 4b26c27e..9845fd4b 100644
--- a/Octokit.Tests/Http/ApiConnectionTests.cs
+++ b/Octokit.Tests/Http/ApiConnectionTests.cs
@@ -87,13 +87,8 @@ namespace Octokit.Tests.Http
             public async Task MakesGetRequestForAllItems()
             {
                 var getAllUri = new Uri("anything", UriKind.Relative);
-                var links = new Dictionary<string, Uri>();
-                var scopes = new List<string>();
                 IApiResponse<List<object>> response = new ApiResponse<List<object>>(
-                    new Response
-                    {
-                        ApiInfo = new ApiInfo(links, scopes, scopes, "etag", new RateLimit(new Dictionary<string, string>()))
-                    },
+                    new Response(),
                     new List<object> { new object(), new object() });
                 var connection = Substitute.For<IConnection>();
                 connection.Get<List<object>>(Args.Uri, null, null).Returns(Task.FromResult(response));
diff --git a/Octokit.Tests/Http/ApiInfoParserTests.cs b/Octokit.Tests/Http/ApiInfoParserTests.cs
index 20b9792c..5fbb3bf1 100644
--- a/Octokit.Tests/Http/ApiInfoParserTests.cs
+++ b/Octokit.Tests/Http/ApiInfoParserTests.cs
@@ -3,7 +3,6 @@ using System.Collections.Generic;
 using System.Linq;
 using Octokit.Internal;
 using Xunit;
-using Xunit.Extensions;
 
 namespace Octokit.Tests
 {
@@ -14,21 +13,17 @@ namespace Octokit.Tests
             [Fact]
             public void ParsesApiInfoFromHeaders()
             {
-                var response = new Response
+                var headers = new Dictionary<string, string>
                 {
-                    Headers =
-                    {
-                        { "X-Accepted-OAuth-Scopes", "user" },
-                        { "X-OAuth-Scopes", "user, public_repo, repo, gist" },
-                        { "X-RateLimit-Limit", "5000" },
-                        { "X-RateLimit-Remaining", "4997" },
-                        { "ETag", "5634b0b187fd2e91e3126a75006cc4fa" }
-                    }
+                    { "X-Accepted-OAuth-Scopes", "user" },
+                    { "X-OAuth-Scopes", "user, public_repo, repo, gist" },
+                    { "X-RateLimit-Limit", "5000" },
+                    { "X-RateLimit-Remaining", "4997" },
+                    { "ETag", "5634b0b187fd2e91e3126a75006cc4fa" }
                 };
 
-                ApiInfoParser.ParseApiHttpHeaders(response);
+                var apiInfo = ApiInfoParser.ParseResponseHeaders(headers);
 
-                var apiInfo = response.ApiInfo;
                 Assert.NotNull(apiInfo);
                 Assert.Equal(new[] { "user" }, apiInfo.AcceptedOauthScopes.ToArray());
                 Assert.Equal(new[] { "user", "public_repo", "repo", "gist" }, apiInfo.OauthScopes.ToArray());
@@ -40,21 +35,17 @@ namespace Octokit.Tests
             [Fact]
             public void BadHeadersAreIgnored()
             {
-                var response = new Response
+                var headers = new Dictionary<string, string>
                 {
-                    Headers =
                     {
-                        {
-                            "Link",
-                            "<https://api.github.com/repos/rails/rails/issues?page=4&per_page=5>; , " +
-                                "<https://api.github.com/repos/rails/rails/issues?page=131&per_page=5; rel=\"last\""
-                        }
+                        "Link",
+                        "<https://api.github.com/repos/rails/rails/issues?page=4&per_page=5>; , " +
+                        "<https://api.github.com/repos/rails/rails/issues?page=131&per_page=5; rel=\"last\""
                     }
                 };
 
-                ApiInfoParser.ParseApiHttpHeaders(response);
+                var apiInfo = ApiInfoParser.ParseResponseHeaders(headers);
 
-                var apiInfo = response.ApiInfo;
                 Assert.NotNull(apiInfo);
                 Assert.Equal(0, apiInfo.Links.Count);
             }
@@ -62,23 +53,19 @@ namespace Octokit.Tests
             [Fact]
             public void ParsesLinkHeader()
             {
-                var response = new Response
+                var headers = new Dictionary<string, string>
                 {
-                    Headers =
                     {
-                        {
-                            "Link",
-                            "<https://api.github.com/repos/rails/rails/issues?page=4&per_page=5>; rel=\"next\", " +
-                            "<https://api.github.com/repos/rails/rails/issues?page=131&per_page=5>; rel=\"last\", " +
-                            "<https://api.github.com/repos/rails/rails/issues?page=1&per_page=5>; rel=\"first\", " +
-                            "<https://api.github.com/repos/rails/rails/issues?page=2&per_page=5>; rel=\"prev\""
-                        }
+                        "Link",
+                        "<https://api.github.com/repos/rails/rails/issues?page=4&per_page=5>; rel=\"next\", " +
+                        "<https://api.github.com/repos/rails/rails/issues?page=131&per_page=5>; rel=\"last\", " +
+                        "<https://api.github.com/repos/rails/rails/issues?page=1&per_page=5>; rel=\"first\", " +
+                        "<https://api.github.com/repos/rails/rails/issues?page=2&per_page=5>; rel=\"prev\""
                     }
                 };
 
-                ApiInfoParser.ParseApiHttpHeaders(response);
+                var apiInfo = ApiInfoParser.ParseResponseHeaders(headers);
 
-                var apiInfo = response.ApiInfo;
                 Assert.NotNull(apiInfo);
                 Assert.Equal(4, apiInfo.Links.Count);
                 Assert.Contains("next", apiInfo.Links.Keys);
diff --git a/Octokit.Tests/Http/ConnectionTests.cs b/Octokit.Tests/Http/ConnectionTests.cs
index 81bd6406..30747fdf 100644
--- a/Octokit.Tests/Http/ConnectionTests.cs
+++ b/Octokit.Tests/Http/ConnectionTests.cs
@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using System.IO;
 using System.Linq;
 using System.Net;
@@ -66,14 +67,12 @@ namespace Octokit.Tests.Http
             public async Task ParsesApiInfoOnResponse()
             {
                 var httpClient = Substitute.For<IHttpClient>();
-                IResponse response = new Response
+                var headers = new Dictionary<string, string>
                 {
-                    Headers =
-                    {
-                        { "X-Accepted-OAuth-Scopes", "user" },
-                    }
+                    { "X-Accepted-OAuth-Scopes", "user" },
                 };
-
+                IResponse response = new Response(headers);
+                
                 httpClient.Send(Args.Request, Args.CancellationToken).Returns(Task.FromResult(response));
                 var connection = new Connection(new ProductHeaderValue("OctokitTests"),
                     _exampleUri,
diff --git a/Octokit.Tests/Models/ReadOnlyPagedCollectionTests.cs b/Octokit.Tests/Models/ReadOnlyPagedCollectionTests.cs
index 8d2a20bc..2618e60c 100644
--- a/Octokit.Tests/Models/ReadOnlyPagedCollectionTests.cs
+++ b/Octokit.Tests/Models/ReadOnlyPagedCollectionTests.cs
@@ -19,11 +19,9 @@ namespace Octokit.Tests.Models
                     new ApiResponse<List<object>>(new Response(), new List<object> {new object(), new object()}));
                 var links = new Dictionary<string, Uri> {{"next", nextPageUrl}};
                 var scopes = new List<string>();
-
-                var response = new ApiResponse<List<object>>(new Response
-                {
-                    ApiInfo = new ApiInfo(links, scopes, scopes, "etag", new RateLimit(new Dictionary<string, string>()))
-                }, new List<object>());
+                var httpResponse = Substitute.For<IResponse>();
+                httpResponse.ApiInfo.Returns(new ApiInfo(links, scopes, scopes, "etag", new RateLimit(new Dictionary<string, string>())));
+                var response = new ApiResponse<List<object>>(httpResponse, new List<object>());
                 var connection = Substitute.For<IConnection>();
                 connection.Get<List<object>>(nextPageUrl, null, null).Returns(nextPageResponse);
                 var pagedCollection = new ReadOnlyPagedCollection<object>(
diff --git a/Octokit.Tests/Reactive/ObservableIssuesClientTests.cs b/Octokit.Tests/Reactive/ObservableIssuesClientTests.cs
index f014de55..58909fcd 100644
--- a/Octokit.Tests/Reactive/ObservableIssuesClientTests.cs
+++ b/Octokit.Tests/Reactive/ObservableIssuesClientTests.cs
@@ -46,18 +46,19 @@ public class ObservableIssuesClientTests
             var firstPageLinks = new Dictionary<string, Uri> { { "next", secondPageUrl } };
             var firstPageResponse = new ApiResponse<List<Issue>>
             (
-                new Response { ApiInfo = CreateApiInfo(firstPageLinks) },
+                CreateResponseWithApiInfo(firstPageLinks),
                 new List<Issue>
                 {
                     CreateIssue(1),
                     CreateIssue(2),
                     CreateIssue(3)
-                });
+                }
+            );
             var thirdPageUrl = new Uri("https://example.com/page/3");
             var secondPageLinks = new Dictionary<string, Uri> { { "next", thirdPageUrl } };
             var secondPageResponse = new ApiResponse<List<Issue>>
             (
-                new Response { ApiInfo = CreateApiInfo(secondPageLinks) },
+                CreateResponseWithApiInfo(secondPageLinks),
                 new List<Issue>
                 {
                     CreateIssue(4),
@@ -67,7 +68,7 @@ public class ObservableIssuesClientTests
             );
             var lastPageResponse = new ApiResponse<List<Issue>>
             (
-                new Response { ApiInfo = CreateApiInfo(new Dictionary<string, Uri>()) },
+                new Response(),
                 new List<Issue>
                 {
                     CreateIssue(7)
@@ -106,7 +107,7 @@ public class ObservableIssuesClientTests
             var firstPageLinks = new Dictionary<string, Uri> { { "next", secondPageUrl } };
             var firstPageResponse = new ApiResponse<List<Issue>>
             (
-                new Response { ApiInfo = CreateApiInfo(firstPageLinks) },
+                CreateResponseWithApiInfo(firstPageLinks),
                 new List<Issue>
                 {
                     CreateIssue(1),
@@ -118,7 +119,7 @@ public class ObservableIssuesClientTests
             var secondPageLinks = new Dictionary<string, Uri> { { "next", thirdPageUrl } };
             var secondPageResponse = new ApiResponse<List<Issue>>
             (
-                new Response { ApiInfo = CreateApiInfo(secondPageLinks) },
+                CreateResponseWithApiInfo(secondPageLinks),
                 new List<Issue>
                 {
                     CreateIssue(4),
@@ -128,10 +129,10 @@ public class ObservableIssuesClientTests
             );
             var lastPageResponse = new ApiResponse<List<Issue>>
             (
-                new Response { ApiInfo = CreateApiInfo(new Dictionary<string, Uri>()) },
+                new Response(),
                 new List<Issue>
                 {
-                    CreateIssue(7 )
+                    CreateIssue(7)
                 }
             );
             var gitHubClient = Substitute.For<IGitHubClient>();
@@ -167,7 +168,7 @@ public class ObservableIssuesClientTests
             var firstPageLinks = new Dictionary<string, Uri> { { "next", secondPageUrl } };
             var firstPageResponse = new ApiResponse<List<Issue>>
             (
-                new Response { ApiInfo = CreateApiInfo(firstPageLinks) },
+                CreateResponseWithApiInfo(firstPageLinks),
                 new List<Issue>
                 {
                     CreateIssue(1),
@@ -179,7 +180,7 @@ public class ObservableIssuesClientTests
             var secondPageLinks = new Dictionary<string, Uri> { { "next", thirdPageUrl } };
             var secondPageResponse = new ApiResponse<List<Issue>>
             (
-                new Response { ApiInfo = CreateApiInfo(secondPageLinks) },
+                CreateResponseWithApiInfo(secondPageLinks),
                 new List<Issue>
                 {
                     CreateIssue(4),
@@ -189,7 +190,7 @@ public class ObservableIssuesClientTests
             );
             var lastPageResponse = new ApiResponse<List<Issue>>
             (
-                new Response { ApiInfo = CreateApiInfo(new Dictionary<string, Uri>()) },
+                new Response(),
                 new List<Issue>
                 {
                     CreateIssue(7)
@@ -228,19 +229,19 @@ public class ObservableIssuesClientTests
             var firstPageLinks = new Dictionary<string, Uri> { { "next", secondPageUrl } };
             var firstPageResponse = new ApiResponse<List<Issue>>
             (
-                new Response { ApiInfo = CreateApiInfo(firstPageLinks) },
+                CreateResponseWithApiInfo(firstPageLinks),
                 new List<Issue>
                 {
                     CreateIssue(1),
                     CreateIssue(2),
-                    CreateIssue(3),
+                    CreateIssue(3)
                 }
             );
             var thirdPageUrl = new Uri("https://example.com/page/3");
             var secondPageLinks = new Dictionary<string, Uri> { { "next", thirdPageUrl } };
             var secondPageResponse = new ApiResponse<List<Issue>>
             (
-                new Response { ApiInfo = CreateApiInfo(secondPageLinks) },
+                CreateResponseWithApiInfo(secondPageLinks),
                 new List<Issue>
                 {
                     CreateIssue(4),
@@ -250,10 +251,10 @@ public class ObservableIssuesClientTests
             );
             var lastPageResponse = new ApiResponse<List<Issue>>
             (
-                new Response { ApiInfo = CreateApiInfo(new Dictionary<string, Uri>()) },
+                new Response(),
                 new List<Issue>
                 {
-                    CreateIssue(7),
+                    CreateIssue(7)
                 }
             );
             var gitHubClient = Substitute.For<IGitHubClient>();
@@ -344,14 +345,17 @@ public class ObservableIssuesClientTests
         }
     }
 
-    static ApiInfo CreateApiInfo(IDictionary<string, Uri> links)
-    {
-        return new ApiInfo(links, new List<string>(), new List<string>(), "etag", new RateLimit(new Dictionary<string, string>()));
-    }
-
     static Issue CreateIssue(int issueNumber)
     {
         var serializer = new SimpleJsonSerializer();
         return serializer.Deserialize<Issue>(@"{""number"": """ + issueNumber + @"""}");
     }
+
+    static IResponse CreateResponseWithApiInfo(IDictionary<string, Uri> links)
+    {
+        var apiInfo = new ApiInfo(links, new List<string>(), new List<string>(), "etag", new RateLimit(new Dictionary<string, string>()));
+        var response = Substitute.For<IResponse>();
+        response.ApiInfo.Returns(apiInfo);
+        return response;
+    }
 }
diff --git a/Octokit.Tests/Reactive/ObservableMilestonesClientTests.cs b/Octokit.Tests/Reactive/ObservableMilestonesClientTests.cs
index 1bfe491c..2a6fc711 100644
--- a/Octokit.Tests/Reactive/ObservableMilestonesClientTests.cs
+++ b/Octokit.Tests/Reactive/ObservableMilestonesClientTests.cs
@@ -47,7 +47,7 @@ namespace Octokit.Tests.Reactive
                 var firstPageLinks = new Dictionary<string, Uri> {{"next", secondPageUrl}};
                 var firstPageResponse = new ApiResponse<List<Milestone>>
                 (
-                    new Response { ApiInfo = CreateApiInfo(firstPageLinks) },
+                    CreateResponseWithApiInfo(firstPageLinks),
                     new List<Milestone>
                     {
                         new Milestone {Number = 1},
@@ -59,7 +59,7 @@ namespace Octokit.Tests.Reactive
                 var secondPageLinks = new Dictionary<string, Uri> {{"next", thirdPageUrl}};
                 var secondPageResponse = new ApiResponse<List<Milestone>>
                 (
-                    new Response { ApiInfo = CreateApiInfo(secondPageLinks) },
+                    CreateResponseWithApiInfo(secondPageLinks),
                     new List<Milestone>
                     {
                         new Milestone {Number = 4},
@@ -69,7 +69,7 @@ namespace Octokit.Tests.Reactive
                 );
                 var lastPageResponse = new ApiResponse<List<Milestone>>
                 (
-                    new Response { ApiInfo = CreateApiInfo(new Dictionary<string, Uri>()) },
+                    new Response(),
                     new List<Milestone>
                     {
                         new Milestone {Number = 7},
@@ -100,7 +100,7 @@ namespace Octokit.Tests.Reactive
                 var firstPageLinks = new Dictionary<string, Uri> {{"next", secondPageUrl}};
                 var firstPageResponse = new ApiResponse<List<Milestone>>
                 (
-                    new Response { ApiInfo = CreateApiInfo(firstPageLinks) },
+                    CreateResponseWithApiInfo(firstPageLinks),
                     new List<Milestone>
                     {
                         new Milestone {Number = 1},
@@ -112,7 +112,7 @@ namespace Octokit.Tests.Reactive
                 var secondPageLinks = new Dictionary<string, Uri> {{"next", thirdPageUrl}};
                 var secondPageResponse = new ApiResponse<List<Milestone>>
                 (
-                    new Response { ApiInfo = CreateApiInfo(secondPageLinks) },
+                    CreateResponseWithApiInfo(secondPageLinks),
                     new List<Milestone>
                     {
                         new Milestone {Number = 4},
@@ -122,7 +122,7 @@ namespace Octokit.Tests.Reactive
                 );
                 var lastPageResponse = new ApiResponse<List<Milestone>>
                 (
-                    new Response { ApiInfo = CreateApiInfo(new Dictionary<string, Uri>()) },
+                    new Response(),
                     new List<Milestone>
                     {
                         new Milestone {Number = 7},
@@ -241,9 +241,11 @@ namespace Octokit.Tests.Reactive
             }
         }
 
-        static ApiInfo CreateApiInfo(IDictionary<string, Uri> links)
+        static IResponse CreateResponseWithApiInfo(IDictionary<string, Uri> links)
         {
-            return new ApiInfo(links, new List<string>(), new List<string>(), "etag", new RateLimit(new Dictionary<string, string>()));
+            var response = Substitute.For<IResponse>();
+            response.ApiInfo.Returns(new ApiInfo(links, new List<string>(), new List<string>(), "etag", new RateLimit(new Dictionary<string, string>())));
+            return response;
         }
     }
 }
diff --git a/Octokit.Tests/Reactive/ObservablePullRequestReviewCommentsClientTests.cs b/Octokit.Tests/Reactive/ObservablePullRequestReviewCommentsClientTests.cs
index c83cd2fd..10b0343d 100644
--- a/Octokit.Tests/Reactive/ObservablePullRequestReviewCommentsClientTests.cs
+++ b/Octokit.Tests/Reactive/ObservablePullRequestReviewCommentsClientTests.cs
@@ -12,9 +12,11 @@ namespace Octokit.Tests.Reactive
 {
     public class ObservablePullRequestReviewCommentsClientTests
     {
-        static ApiInfo CreateApiInfo(IDictionary<string, Uri> links)
+        static IResponse CreateResponseWithApiInfo(IDictionary<string, Uri> links)
         {
-            return new ApiInfo(links, new List<string>(), new List<string>(), "etag", new RateLimit(new Dictionary<string, string>()));
+            var response = Substitute.For<IResponse>();
+            response.ApiInfo.Returns(new ApiInfo(links, new List<string>(), new List<string>(), "etag", new RateLimit(new Dictionary<string, string>())));
+            return response;
         }
 
         public class TheGetForPullRequestMethod
@@ -27,7 +29,7 @@ namespace Octokit.Tests.Reactive
                 var firstPageLinks = new Dictionary<string, Uri> { { "next", secondPageUrl } };
                 var firstPageResponse = new ApiResponse<List<PullRequestReviewComment>>
                 (
-                    new Response { ApiInfo = CreateApiInfo(firstPageLinks) },
+                    CreateResponseWithApiInfo(firstPageLinks),
                     new List<PullRequestReviewComment>
                     {
                         new PullRequestReviewComment {Id = 1},
@@ -38,7 +40,7 @@ namespace Octokit.Tests.Reactive
                 var secondPageLinks = new Dictionary<string, Uri> { { "next", thirdPageUrl } };
                 var secondPageResponse = new ApiResponse<List<PullRequestReviewComment>>
                 (
-                    new Response { ApiInfo = CreateApiInfo(secondPageLinks) },
+                    CreateResponseWithApiInfo(secondPageLinks),
                     new List<PullRequestReviewComment>
                     {
                         new PullRequestReviewComment {Id = 4},
@@ -48,7 +50,7 @@ namespace Octokit.Tests.Reactive
                 );
                 var lastPageResponse = new ApiResponse<List<PullRequestReviewComment>>
                 (
-                    new Response { ApiInfo = CreateApiInfo(new Dictionary<string, Uri>()) },
+                    new Response(),
                     new List<PullRequestReviewComment>
                     {
                         new PullRequestReviewComment {Id = 7}
@@ -98,7 +100,7 @@ namespace Octokit.Tests.Reactive
                 var firstPageLinks = new Dictionary<string, Uri> { { "next", secondPageUrl } };
                 var firstPageResponse = new ApiResponse<List<PullRequestReviewComment>>
                 (
-                    new Response { ApiInfo = CreateApiInfo(firstPageLinks) },
+                    CreateResponseWithApiInfo(firstPageLinks),
                     new List<PullRequestReviewComment>
                     {
                         new PullRequestReviewComment {Id = 1},
@@ -110,7 +112,7 @@ namespace Octokit.Tests.Reactive
                 var secondPageLinks = new Dictionary<string, Uri> { { "next", thirdPageUrl } };
                 var secondPageResponse = new ApiResponse<List<PullRequestReviewComment>>
                 (
-                    new Response { ApiInfo = CreateApiInfo(secondPageLinks) },
+                    CreateResponseWithApiInfo(secondPageLinks),
                     new List<PullRequestReviewComment>
                     {
                         new PullRequestReviewComment {Id = 4},
@@ -119,7 +121,7 @@ namespace Octokit.Tests.Reactive
                     });
                 var lastPageResponse = new ApiResponse<List<PullRequestReviewComment>>
                 (
-                    new Response { ApiInfo = CreateApiInfo(new Dictionary<string, Uri>()) },
+                    new Response(),
                     new List<PullRequestReviewComment>
                     {
                         new PullRequestReviewComment {Id = 7},
@@ -169,7 +171,7 @@ namespace Octokit.Tests.Reactive
                 var firstPageLinks = new Dictionary<string, Uri> { { "next", secondPageUrl } };
                 var firstPageResponse = new ApiResponse<List<PullRequestReviewComment>>
                 (
-                    new Response { ApiInfo = CreateApiInfo(firstPageLinks) },
+                    CreateResponseWithApiInfo(firstPageLinks),
                     new List<PullRequestReviewComment>
                     {
                         new PullRequestReviewComment {Id = 1},
@@ -181,7 +183,7 @@ namespace Octokit.Tests.Reactive
                 var secondPageLinks = new Dictionary<string, Uri> { { "next", thirdPageUrl } };
                 var secondPageResponse = new ApiResponse<List<PullRequestReviewComment>>
                 (
-                    new Response { ApiInfo = CreateApiInfo(secondPageLinks) },
+                    CreateResponseWithApiInfo(secondPageLinks),
                     new List<PullRequestReviewComment>
                     {
                         new PullRequestReviewComment {Id = 4},
@@ -190,7 +192,7 @@ namespace Octokit.Tests.Reactive
                     });
                 var lastPageResponse = new ApiResponse<List<PullRequestReviewComment>>
                 (
-                    new Response { ApiInfo = CreateApiInfo(new Dictionary<string, Uri>()) },               
+                    new Response(),               
                     new List<PullRequestReviewComment>
                     {
                         new PullRequestReviewComment {Id = 7},
diff --git a/Octokit.Tests/Reactive/ObservablePullRequestsClientTests.cs b/Octokit.Tests/Reactive/ObservablePullRequestsClientTests.cs
index e074574c..054a2ffd 100644
--- a/Octokit.Tests/Reactive/ObservablePullRequestsClientTests.cs
+++ b/Octokit.Tests/Reactive/ObservablePullRequestsClientTests.cs
@@ -47,7 +47,7 @@ namespace Octokit.Tests.Reactive
                 var firstPageLinks = new Dictionary<string, Uri> { { "next", secondPageUrl } };
                 var firstPageResponse = new ApiResponse<List<PullRequest>>
                 (
-                    new Response { ApiInfo = CreateApiInfo(firstPageLinks) },
+                    CreateResponseWithApiInfo(firstPageLinks),
                     new List<PullRequest>
                     {
                         new PullRequest {Number = 1},
@@ -59,7 +59,7 @@ namespace Octokit.Tests.Reactive
                 var secondPageLinks = new Dictionary<string, Uri> { { "next", thirdPageUrl } };
                 var secondPageResponse = new ApiResponse<List<PullRequest>>
                 (
-                    new Response { ApiInfo = CreateApiInfo(secondPageLinks) },
+                    CreateResponseWithApiInfo(secondPageLinks),
                     new List<PullRequest>
                     {
                         new PullRequest {Number = 4},
@@ -69,7 +69,7 @@ namespace Octokit.Tests.Reactive
                 );
                 var lastPageResponse = new ApiResponse<List<PullRequest>>
                 (
-                    new Response { ApiInfo = CreateApiInfo(new Dictionary<string, Uri>()) },
+                    new Response(),
                     new List<PullRequest>
                     {
                         new PullRequest {Number = 7},
@@ -100,7 +100,7 @@ namespace Octokit.Tests.Reactive
                 var firstPageLinks = new Dictionary<string, Uri> { { "next", secondPageUrl } };
                 var firstPageResponse = new ApiResponse<List<PullRequest>>
                 (
-                    new Response { ApiInfo = CreateApiInfo(firstPageLinks) },
+                    CreateResponseWithApiInfo(firstPageLinks),
                     new List<PullRequest>
                     {
                         new PullRequest {Number = 1},
@@ -112,7 +112,7 @@ namespace Octokit.Tests.Reactive
                 var secondPageLinks = new Dictionary<string, Uri> { { "next", thirdPageUrl } };
                 var secondPageResponse = new ApiResponse<List<PullRequest>>
                 (
-                    new Response { ApiInfo = CreateApiInfo(secondPageLinks) },
+                    CreateResponseWithApiInfo(secondPageLinks),
                     new List<PullRequest>
                     {
                         new PullRequest {Number = 4},
@@ -122,7 +122,7 @@ namespace Octokit.Tests.Reactive
                 );
                 var lastPageResponse = new ApiResponse<List<PullRequest>>
                 (
-                    new Response { ApiInfo = CreateApiInfo(new Dictionary<string, Uri>()) },
+                    new Response(),
                     new List<PullRequest>
                     {
                         new PullRequest {Number = 7},
@@ -282,12 +282,7 @@ namespace Octokit.Tests.Reactive
                 var connection = Substitute.For<IConnection>();
                 IApiResponse<List<PullRequestCommit>> response = new ApiResponse<List<PullRequestCommit>>
                 (
-                    new Response { ApiInfo = new ApiInfo(
-                        new Dictionary<string, Uri>(),
-                        new List<string>(),
-                        new List<string>(),
-                        "",
-                        new RateLimit(new Dictionary<string, string>()))},
+                    new Response(),
                     new List<PullRequestCommit> { commit }
                 );
                 connection.Get<List<PullRequestCommit>>(Args.Uri, null, null)
@@ -324,9 +319,11 @@ namespace Octokit.Tests.Reactive
             }
         }
 
-        static ApiInfo CreateApiInfo(IDictionary<string, Uri> links)
+        static IResponse CreateResponseWithApiInfo(IDictionary<string, Uri> links)
         {
-            return new ApiInfo(links, new List<string>(), new List<string>(), "etag", new RateLimit(new Dictionary<string, string>()));
+            var response = Substitute.For<IResponse>();
+            response.ApiInfo.Returns(new ApiInfo(links, new List<string>(), new List<string>(), "etag", new RateLimit(new Dictionary<string, string>())));
+            return response;
         }
     }
 }
diff --git a/Octokit.Tests/Reactive/ObservableRepositoriesClientTests.cs b/Octokit.Tests/Reactive/ObservableRepositoriesClientTests.cs
index 47f72b0b..21349be3 100644
--- a/Octokit.Tests/Reactive/ObservableRepositoriesClientTests.cs
+++ b/Octokit.Tests/Reactive/ObservableRepositoriesClientTests.cs
@@ -49,7 +49,7 @@ namespace Octokit.Tests.Reactive
                 var secondPageUrl = new Uri("https://example.com/page/2");
                 var firstPageLinks = new Dictionary<string, Uri> {{"next", secondPageUrl}};
                 var firstPageResponse = new ApiResponse<List<Repository>>(
-                    new Response { ApiInfo = CreateApiInfo(firstPageLinks) },
+                    CreateResponseWithApiInfo(firstPageLinks),
                     new List<Repository>
                     {
                         new Repository { Id = 1 },
@@ -60,7 +60,7 @@ namespace Octokit.Tests.Reactive
                 var secondPageLinks = new Dictionary<string, Uri> {{"next", thirdPageUrl}};
                 var secondPageResponse = new ApiResponse<List<Repository>>
                 (
-                    new Response { ApiInfo = CreateApiInfo(secondPageLinks) },
+                    CreateResponseWithApiInfo(secondPageLinks),
                     new List<Repository>
                     {
                         new Repository {Id = 4},
@@ -68,7 +68,7 @@ namespace Octokit.Tests.Reactive
                         new Repository {Id = 6}
                     });
                 var lastPageResponse = new ApiResponse<List<Repository>>(
-                    new Response { ApiInfo = CreateApiInfo(new Dictionary<string, Uri>()) },
+                    new Response(),
                     new List<Repository>
                     {
                         new Repository { Id = 7 }
@@ -98,7 +98,7 @@ namespace Octokit.Tests.Reactive
                 var firstPageLinks = new Dictionary<string, Uri> { { "next", secondPageUrl } };
                 var firstPageResponse = new ApiResponse<List<Repository>>
                 (
-                    new Response { ApiInfo = CreateApiInfo(firstPageLinks) },
+                    CreateResponseWithApiInfo(firstPageLinks),
                     new List<Repository>
                     {
                         new Repository {Id = 1},
@@ -110,7 +110,7 @@ namespace Octokit.Tests.Reactive
                 var secondPageLinks = new Dictionary<string, Uri> { { "next", thirdPageUrl } };
                 var secondPageResponse = new ApiResponse<List<Repository>>
                 (
-                    new Response { ApiInfo = CreateApiInfo(secondPageLinks) },
+                    CreateResponseWithApiInfo(secondPageLinks),
                     new List<Repository>
                     {
                         new Repository {Id = 4},
@@ -123,7 +123,7 @@ namespace Octokit.Tests.Reactive
                 var thirdPageResponse = new ApiResponse<List<Repository>>
                 (
                     
-                    new Response { ApiInfo = CreateApiInfo(thirdPageLinks) },
+                    CreateResponseWithApiInfo(thirdPageLinks),
                     new List<Repository>
                     {
                         new Repository {Id = 7}
@@ -131,7 +131,7 @@ namespace Octokit.Tests.Reactive
                 );
                 var lastPageResponse = new ApiResponse<List<Repository>>
                 (
-                    new Response { ApiInfo = CreateApiInfo(new Dictionary<string, Uri>()) },
+                    new Response(),
                     new List<Repository>
                     {
                         new Repository {Id = 8}
@@ -408,9 +408,11 @@ namespace Octokit.Tests.Reactive
             }
         }
 
-        static ApiInfo CreateApiInfo(IDictionary<string, Uri> links)
+        static IResponse CreateResponseWithApiInfo(IDictionary<string, Uri> links)
         {
-            return new ApiInfo(links, new List<string>(), new List<string>(), "etag", new RateLimit(new Dictionary<string, string>()));
+            var response = Substitute.For<IResponse>();
+            response.ApiInfo.Returns(new ApiInfo(links, new List<string>(), new List<string>(), "etag", new RateLimit(new Dictionary<string, string>())));
+            return response;
         }
     }
 }
diff --git a/Octokit/Http/ApiInfoParser.cs b/Octokit/Http/ApiInfoParser.cs
index be87292f..c0878be9 100644
--- a/Octokit/Http/ApiInfoParser.cs
+++ b/Octokit/Http/ApiInfoParser.cs
@@ -5,7 +5,7 @@ using System.Text.RegularExpressions;
 
 namespace Octokit.Internal
 {
-    internal static class ApiInfoParser
+    public static class ApiInfoParser
     {
         const RegexOptions regexOptions =
 #if NETFX_CORE
@@ -17,21 +17,7 @@ namespace Octokit.Internal
         static readonly Regex _linkRelRegex = new Regex("rel=\"(next|prev|first|last)\"", regexOptions);
         static readonly Regex _linkUriRegex = new Regex("<(.+)>", regexOptions);
 
-        public static void ParseApiHttpHeaders(IResponse response)
-        {
-            Ensure.ArgumentNotNull(response, "response");
-
-            response.ApiInfo = ParseHeaders(response);
-        }
-
-        static ApiInfo ParseHeaders(IResponse response)
-        {
-            Ensure.ArgumentNotNull(response, "response");
-
-            return ParseResponseHeaders(response.Headers);
-        }
-
-        static ApiInfo ParseResponseHeaders(IDictionary<string, string> responseHeaders)
+        public static ApiInfo ParseResponseHeaders(IDictionary<string, string> responseHeaders)
         {
             Ensure.ArgumentNotNull(responseHeaders, "responseHeaders");
 
diff --git a/Octokit/Http/ApiResponse.cs b/Octokit/Http/ApiResponse.cs
index a71198d6..e68f8a6f 100644
--- a/Octokit/Http/ApiResponse.cs
+++ b/Octokit/Http/ApiResponse.cs
@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Collections.ObjectModel;
 using System.Net;
 
 namespace Octokit.Internal
@@ -16,9 +17,8 @@ namespace Octokit.Internal
 
             var body = response.Body is T ? (T)response.Body : default(T);
             HttpResponse = response;
-            Headers = response.Headers;
+            Headers = new ReadOnlyDictionary<string, string>(response.Headers);
             Body = body;
-            ResponseUri = response.ResponseUri;
             ApiInfo = response.ApiInfo;
             StatusCode = response.StatusCode;
             ContentType = response.ContentType;
@@ -26,8 +26,7 @@ namespace Octokit.Internal
         }
 
         public T Body { get; private set; }
-        public Dictionary<string, string> Headers { get; private set; }
-        public Uri ResponseUri { get; set; }
+        public IReadOnlyDictionary<string, string> Headers { get; private set; }
         public ApiInfo ApiInfo { get; set; }
         public HttpStatusCode StatusCode { get; set; }
         public IResponse HttpResponse { get; private set; }
diff --git a/Octokit/Http/Connection.cs b/Octokit/Http/Connection.cs
index b953c446..8875666f 100644
--- a/Octokit/Http/Connection.cs
+++ b/Octokit/Http/Connection.cs
@@ -432,7 +432,6 @@ namespace Octokit
             request.Headers.Add("User-Agent", UserAgent);
             await _authenticator.Apply(request).ConfigureAwait(false);
             var response = await _httpClient.Send(request, cancellationToken).ConfigureAwait(false);
-            ApiInfoParser.ParseApiHttpHeaders(response);
             HandleErrors(response);
             return response;
         }
diff --git a/Octokit/Http/HttpClientAdapter.cs b/Octokit/Http/HttpClientAdapter.cs
index 0ea7f2da..b2540cec 100644
--- a/Octokit/Http/HttpClientAdapter.cs
+++ b/Octokit/Http/HttpClientAdapter.cs
@@ -88,19 +88,12 @@ namespace Octokit.Internal
                 }
             }
 
-            var response = new Response
+            return new Response(responseMessage.Headers.ToDictionary(h => h.Key, h => h.Value.First()))
             {
                 Body = responseBody,
                 StatusCode = responseMessage.StatusCode,
-                ContentType = contentType
+                ContentType = contentType,
             };
-
-            foreach (var h in responseMessage.Headers)
-            {
-                response.Headers.Add(h.Key, h.Value.First());
-            }
-
-            return response;
         }
 
         protected virtual HttpRequestMessage BuildRequestMessage(IRequest request)
diff --git a/Octokit/Http/IResponse.cs b/Octokit/Http/IResponse.cs
index c2e65f72..1cb48260 100644
--- a/Octokit/Http/IResponse.cs
+++ b/Octokit/Http/IResponse.cs
@@ -18,10 +18,9 @@ namespace Octokit
     public interface IResponse
     {
         object Body { get; }
-        Dictionary<string, string> Headers { get; }
-        Uri ResponseUri { get; set; }
-        ApiInfo ApiInfo { get; set; }
-        HttpStatusCode StatusCode { get; set; }
-        string ContentType { get; set; }
+        IDictionary<string, string> Headers { get; }
+        ApiInfo ApiInfo { get; }
+        HttpStatusCode StatusCode { get; }
+        string ContentType { get; }
     }
 }
diff --git a/Octokit/Http/Response.cs b/Octokit/Http/Response.cs
index 397b13fe..dc8437c5 100644
--- a/Octokit/Http/Response.cs
+++ b/Octokit/Http/Response.cs
@@ -1,20 +1,27 @@
 using System;
 using System.Collections.Generic;
 using System.Net;
+using Octokit.Internal;
 
 namespace Octokit.Internal
 {
     public class Response : IResponse
     {
-        public Response()
+        public Response() : this(new Dictionary<string, string>())
         {
-            Headers = new Dictionary<string, string>();
+        }
+
+        public Response(IDictionary<string, string> headers)
+        {
+            Ensure.ArgumentNotNull(headers, "headers");
+
+            Headers = headers;
+            ApiInfo = ApiInfoParser.ParseResponseHeaders(headers);
         }
 
         public object Body { get; set; }
-        public Dictionary<string, string> Headers { get; private set; }
-        public Uri ResponseUri { get; set; }
-        public ApiInfo ApiInfo { get; set; }
+        public IDictionary<string, string> Headers { get; private set; }
+        public ApiInfo ApiInfo { get; private set; }
         public HttpStatusCode StatusCode { get; set; }
         public string ContentType { get; set; }
     }