diff --git a/Octokit.Tests/Clients/OrganizationMembersClientTests.cs b/Octokit.Tests/Clients/OrganizationMembersClientTests.cs
new file mode 100644
index 00000000..04f35e38
--- /dev/null
+++ b/Octokit.Tests/Clients/OrganizationMembersClientTests.cs
@@ -0,0 +1,294 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Net;
+using System.Text;
+using System.Threading.Tasks;
+using NSubstitute;
+using Octokit.Clients;
+using Octokit.Internal;
+using Octokit.Tests.Helpers;
+using Xunit;
+using Xunit.Extensions;
+
+namespace Octokit.Tests.Clients
+{
+    /// <summary>
+    /// Client tests mostly just need to make sure they call the IApiConnection with the correct 
+    /// relative Uri. No need to fake up the response. All *those* tests are in ApiConnectionTests.cs.
+    /// </summary>
+    public class OrganizationMembersClientTests
+    {
+        public class TheConstructor
+        {
+            [Fact]
+            public void EnsureNonNullArguments()
+            {
+                Assert.Throws<ArgumentNullException>(() => new OrganizationMembersClient(null));
+            }
+        }
+
+        public class TheGetAllMethod
+        {
+            [Fact]
+            public void RequestsTheCorrectUrl()
+            {
+                var client = Substitute.For<IApiConnection>();
+                var orgMembersClient = new OrganizationMembersClient(client);
+
+                orgMembersClient.GetAll("org");
+
+                client.Received().GetAll<User>(Arg.Is<Uri>(u => u.ToString() == "orgs/org/members"));
+            }
+
+            [Fact]
+            public void EnsureNonNullArguments()
+            {
+                var orgMembers = new OrganizationMembersClient(Substitute.For<IApiConnection>());
+
+                AssertEx.Throws<ArgumentNullException>(async () => await orgMembers.GetAll(null));
+                AssertEx.Throws<ArgumentException>(async () => await orgMembers.GetAll(""));
+            }
+        }
+
+        public class TheGetPublicMethod
+        {
+            [Fact]
+            public void RequestsTheCorrectUrl()
+            {
+                var client = Substitute.For<IApiConnection>();
+                var orgMembers = new OrganizationMembersClient(client);
+
+                orgMembers.GetPublic("org");
+
+                client.Received().GetAll<User>(Arg.Is<Uri>(u => u.ToString() == "orgs/org/public_members"));
+            }
+
+            [Fact]
+            public void EnsureNonNullArguments()
+            {
+                var orgMembers = new OrganizationMembersClient(Substitute.For<IApiConnection>());
+
+                AssertEx.Throws<ArgumentNullException>(async () => await orgMembers.GetPublic(null));
+                AssertEx.Throws<ArgumentException>(async () => await orgMembers.GetPublic(""));
+            }
+        }
+
+        public class TheCheckMemberMethod
+        {
+            [Theory]
+            [InlineData(HttpStatusCode.NoContent, true)]
+            [InlineData(HttpStatusCode.NotFound, false)]
+            [InlineData(HttpStatusCode.Found, false)]
+            public async Task RequestsCorrectValueForStatusCode(HttpStatusCode status, bool expected)
+            {
+                var response = Task.Factory.StartNew<IResponse<object>>(() =>
+                    new ApiResponse<object> { StatusCode = status });
+                var connection = Substitute.For<IConnection>();
+                connection.GetAsync<object>(Arg.Is<Uri>(u => u.ToString() == "orgs/org/members/username"),
+                    null, null).Returns(response);
+                var apiConnection = Substitute.For<IApiConnection>();
+                apiConnection.Connection.Returns(connection);
+                var client = new OrganizationMembersClient(apiConnection);
+
+                var result = await client.CheckMember("org", "username");
+
+                Assert.Equal(expected, result);
+            }
+
+            [Fact]
+            public async Task ThrowsExceptionForInvalidStatusCode()
+            {
+                var response = Task.Factory.StartNew<IResponse<object>>(() =>
+                    new ApiResponse<object> { StatusCode = HttpStatusCode.Conflict });
+                var connection = Substitute.For<IConnection>();
+                connection.GetAsync<object>(Arg.Is<Uri>(u => u.ToString() == "orgs/org/members/username"),
+                    null, null).Returns(response);
+                var apiConnection = Substitute.For<IApiConnection>();
+                apiConnection.Connection.Returns(connection);
+                var client = new OrganizationMembersClient(apiConnection);
+
+                AssertEx.Throws<ApiException>(async () => await client.CheckMember("org", "username"));
+            }
+
+
+            [Fact]
+            public async Task EnsureNonNullArguments()
+            {
+                var orgMembers = new OrganizationMembersClient(Substitute.For<IApiConnection>());
+
+                await AssertEx.Throws<ArgumentNullException>(async () => await orgMembers.CheckMember(null, "username"));
+                await AssertEx.Throws<ArgumentException>(async () => await orgMembers.CheckMember(null, ""));
+                await AssertEx.Throws<ArgumentNullException>(async () => await orgMembers.CheckMember("org", null));
+                await AssertEx.Throws<ArgumentException>(async () => await orgMembers.CheckMember("", null));
+            }
+        }
+
+        public class TheCheckMemberPublicMethod
+        {
+            [Theory]
+            [InlineData(HttpStatusCode.NoContent, true)]
+            [InlineData(HttpStatusCode.NotFound, false)]
+            public async Task RequestsCorrectValueForStatusCode(HttpStatusCode status, bool expected)
+            {
+                var response = Task.Factory.StartNew<IResponse<object>>(() =>
+                    new ApiResponse<object> { StatusCode = status });
+                var connection = Substitute.For<IConnection>();
+                connection.GetAsync<object>(Arg.Is<Uri>(u => u.ToString() == "orgs/org/public_members/username"),
+                    null, null).Returns(response);
+                var apiConnection = Substitute.For<IApiConnection>();
+                apiConnection.Connection.Returns(connection);
+                var client = new OrganizationMembersClient(apiConnection);
+
+                var result = await client.CheckMemberPublic("org", "username");
+
+                Assert.Equal(expected, result);
+            }
+
+            [Fact]
+            public async Task ThrowsExceptionForInvalidStatusCode()
+            {
+                var response = Task.Factory.StartNew<IResponse<object>>(() =>
+                    new ApiResponse<object> { StatusCode = HttpStatusCode.Conflict });
+                var connection = Substitute.For<IConnection>();
+                connection.GetAsync<object>(Arg.Is<Uri>(u => u.ToString() == "orgs/org/public_members/username"),
+                    null, null).Returns(response);
+                var apiConnection = Substitute.For<IApiConnection>();
+                apiConnection.Connection.Returns(connection);
+                var client = new OrganizationMembersClient(apiConnection);
+
+                AssertEx.Throws<ApiException>(async () => await client.CheckMemberPublic("org", "username"));
+            }
+
+            [Fact]
+            public async Task EnsureNonNullArguments()
+            {
+                var orgMembers = new OrganizationMembersClient(Substitute.For<IApiConnection>());
+
+                await AssertEx.Throws<ArgumentNullException>(async () => await orgMembers.CheckMemberPublic(null, "username"));
+                await AssertEx.Throws<ArgumentException>(async () => await orgMembers.CheckMemberPublic("", "username"));
+                await AssertEx.Throws<ArgumentNullException>(async () => await orgMembers.CheckMemberPublic("org", null));
+                await AssertEx.Throws<ArgumentException>(async () => await orgMembers.CheckMemberPublic("org", ""));
+            }
+        }
+
+        public class TheDeleteMethod
+        {
+            [Fact]
+            public void PostsToCorrectUrl()
+            {
+                var connection = Substitute.For<IApiConnection>();
+                var client = new OrganizationMembersClient(connection);
+
+                client.Delete("org", "username");
+
+                connection.Received().Delete(Arg.Is<Uri>(u => u.ToString() == "orgs/org/members/username"));
+            }
+
+            [Fact]
+            public async Task EnsureNonNullArguments()
+            {
+                var orgMembers = new OrganizationMembersClient(Substitute.For<IApiConnection>());
+
+                await AssertEx.Throws<ArgumentNullException>(async () => await orgMembers.Delete(null, "username"));
+                await AssertEx.Throws<ArgumentException>(async () => await orgMembers.Delete("", "username"));
+                await AssertEx.Throws<ArgumentNullException>(async () => await orgMembers.Delete("org", null));
+                await AssertEx.Throws<ArgumentException>(async () => await orgMembers.Delete("org", ""));
+            }
+        }
+
+        public class ThePublicizeMethod
+        {
+            [Theory]
+            [InlineData(HttpStatusCode.NoContent, true)]
+            public async Task RequestsCorrectValueForStatusCode(HttpStatusCode status, bool expected)
+            {
+                var response = Task.Factory.StartNew<IResponse<object>>(() =>
+                    new ApiResponse<object> { StatusCode = status });
+                var connection = Substitute.For<IConnection>();
+                connection.PutAsync<object>(Arg.Is<Uri>(u => u.ToString() == "orgs/org/public_members/username"),
+                    Args.Object).Returns(response);
+                var apiConnection = Substitute.For<IApiConnection>();
+                apiConnection.Connection.Returns(connection);
+                var client = new OrganizationMembersClient(apiConnection);
+
+                var result = await client.Publicize("org", "username");
+
+                Assert.Equal(expected, result);
+            }
+
+            [Fact]
+            public async Task ThrowsExceptionForInvalidStatusCode()
+            {
+                var response = Task.Factory.StartNew<IResponse<object>>(() =>
+                    new ApiResponse<object> { StatusCode = HttpStatusCode.Conflict });
+                var connection = Substitute.For<IConnection>();
+                connection.PutAsync<object>(Arg.Is<Uri>(u => u.ToString() == "orgs/org/public_members/username"),
+                    new { }).Returns(response);
+                var apiConnection = Substitute.For<IApiConnection>();
+                apiConnection.Connection.Returns(connection);
+                var client = new OrganizationMembersClient(apiConnection);
+
+                AssertEx.Throws<ApiException>(async () => await client.Publicize("org", "username"));
+            }
+
+            [Fact]
+            public async Task EnsureNonNullArguments()
+            {
+                var orgMembers = new OrganizationMembersClient(Substitute.For<IApiConnection>());
+
+                await AssertEx.Throws<ArgumentNullException>(async () => await orgMembers.Publicize(null, "username"));
+                await AssertEx.Throws<ArgumentException>(async () => await orgMembers.Publicize("", "username"));
+                await AssertEx.Throws<ArgumentNullException>(async () => await orgMembers.Publicize("org", null));
+                await AssertEx.Throws<ArgumentException>(async () => await orgMembers.Publicize("org", ""));
+            }
+        }
+
+        public class TheConcealMethod
+        {
+            [Theory]
+            [InlineData(HttpStatusCode.NoContent, true)]
+            public async Task RequestsCorrectValueForStatusCode(HttpStatusCode status, bool expected)
+            {
+                var response = Task.Factory.StartNew<IResponse<object>>(() =>
+                    new ApiResponse<object> { StatusCode = status });
+                var connection = Substitute.For<IConnection>();
+                connection.PutAsync<object>(Arg.Is<Uri>(u => u.ToString() == "orgs/org/public_members/username"),
+                    Args.Object).Returns(response);
+                var apiConnection = Substitute.For<IApiConnection>();
+                apiConnection.Connection.Returns(connection);
+                var client = new OrganizationMembersClient(apiConnection);
+
+                var result = await client.Conceal("org", "username");
+
+                Assert.Equal(expected, result);
+            }
+
+            [Fact]
+            public async Task ThrowsExceptionForInvalidStatusCode()
+            {
+                var response = Task.Factory.StartNew<IResponse<object>>(() =>
+                    new ApiResponse<object> { StatusCode = HttpStatusCode.Conflict });
+                var connection = Substitute.For<IConnection>();
+                connection.PutAsync<object>(Arg.Is<Uri>(u => u.ToString() == "orgs/org/public_members/username"),
+                    new { }).Returns(response);
+                var apiConnection = Substitute.For<IApiConnection>();
+                apiConnection.Connection.Returns(connection);
+                var client = new OrganizationMembersClient(apiConnection);
+
+                AssertEx.Throws<ApiException>(async () => await client.Conceal("org", "username"));
+            }
+
+            [Fact]
+            public async Task EnsureNonNullArguments()
+            {
+                var orgMembers = new OrganizationMembersClient(Substitute.For<IApiConnection>());
+
+                await AssertEx.Throws<ArgumentNullException>(async () => await orgMembers.Conceal(null, "username"));
+                await AssertEx.Throws<ArgumentException>(async () => await orgMembers.Conceal("", "username"));
+                await AssertEx.Throws<ArgumentNullException>(async () => await orgMembers.Conceal("org", null));
+                await AssertEx.Throws<ArgumentException>(async () => await orgMembers.Conceal("org", ""));
+            }
+        }
+    }
+}
diff --git a/Octokit.Tests/Octokit.Tests.csproj b/Octokit.Tests/Octokit.Tests.csproj
index 4cb79a7e..4d660968 100644
--- a/Octokit.Tests/Octokit.Tests.csproj
+++ b/Octokit.Tests/Octokit.Tests.csproj
@@ -65,6 +65,7 @@
     <Compile Include="Clients\AssigneesClientTests.cs" />
     <Compile Include="Clients\CommitStatusClientTests.cs" />
     <Compile Include="Clients\GitDatabaseClientTests.cs" />
+    <Compile Include="Clients\OrganizationMembersClientTests.cs" />
     <Compile Include="Clients\TagsClientTests.cs" />
     <Compile Include="Clients\IssuesEventsClientTests.cs" />
     <Compile Include="Clients\IssueCommentsClientTests.cs" />