diff --git a/Octokit.Tests/Models/DeploymentTests.cs b/Octokit.Tests/Models/DeploymentTests.cs
index d60c9b11..dab6b668 100644
--- a/Octokit.Tests/Models/DeploymentTests.cs
+++ b/Octokit.Tests/Models/DeploymentTests.cs
@@ -8,6 +8,18 @@ namespace Octokit.Tests.Models
 {
     public class DeploymentTests
     {
+        [Fact]
+        public void CanSerialize()
+        {
+            var deployment = new NewDeployment("ref")
+            {
+                Payload = new Dictionary<string, string> {{"environment", "production"}}
+            };
+            var deserialized = new SimpleJsonSerializer().Serialize(deployment);
+            
+            Assert.Equal(@"{""ref"":""ref"",""task"":""deploy"",""payload"":{""environment"":""production""}}", deserialized);
+        }
+
         [Fact]
         public void CanDeserialize()
         {
diff --git a/Octokit/Models/Request/NewDeployment.cs b/Octokit/Models/Request/NewDeployment.cs
index b844ceff..7fdf30d4 100644
--- a/Octokit/Models/Request/NewDeployment.cs
+++ b/Octokit/Models/Request/NewDeployment.cs
@@ -1,4 +1,5 @@
-using System.Collections.ObjectModel;
+using System.Collections.Generic;
+using System.Collections.ObjectModel;
 using System.Diagnostics;
 using System.Diagnostics.CodeAnalysis;
 using System.Globalization;
@@ -59,7 +60,7 @@ namespace Octokit
         /// <summary>
         /// JSON payload with extra information about the deployment.
         /// </summary>
-        public string Payload { get; set; }
+        public Dictionary<string, string> Payload { get; set; }
 
         /// <summary>
         /// Optional name for the target deployment environment (e.g., production, staging, qa). Default: "production"