Index: MvcContrib.TestHelper/MvcContrib.TestHelper/TestControllerBuilder.cs
===================================================================
--- MvcContrib.TestHelper/MvcContrib.TestHelper/TestControllerBuilder.cs	(revision 931)
+++ MvcContrib.TestHelper/MvcContrib.TestHelper/TestControllerBuilder.cs	(working copy)
@@ -19,8 +19,9 @@
 		protected MockRepository _mocks;
 		protected TempDataDictionary _tempData;
         protected System.Web.Caching.Cache _cache;
+	    
 
-		/// <summary>
+	    /// <summary>
 		/// Initializes a new instance of the <see cref="TestControllerBuilder"/> class.
 		/// </summary>
 		public TestControllerBuilder()
@@ -58,6 +59,11 @@
 		/// <value>The NameValueCollection QueryString</value>
 		public NameValueCollection QueryString { get; protected set; }
 
+        /// <summary>
+        /// Gets or sets the AcceptTypes property of Request that built controllers will have set internally when created with InitializeController
+        /// </summary>
+        public string[] AcceptTypes { get; set; }
+
 		/// <summary>
 		/// Gets the Session that built controllers will have set internally when created with InitializeController
 		/// </summary>
@@ -120,6 +126,8 @@
 			Form = new NameValueCollection();
 			SetupResult.For(request.Form).Return(Form);
 
+            SetupResult.For(request.AcceptTypes).Do((Func<string[]>)(() => AcceptTypes));
+
 			var files = new WriteableHttpFileCollection();
 			Files = files;
 			SetupResult.For(request.Files).Return(files);
Index: MVCContrib.UnitTests/TestHelper/ControllerBuilderTests.cs
===================================================================
--- MVCContrib.UnitTests/TestHelper/ControllerBuilderTests.cs	(revision 931)
+++ MVCContrib.UnitTests/TestHelper/ControllerBuilderTests.cs	(working copy)
@@ -106,6 +106,17 @@
 			Assert.AreEqual("someUrl", testController.Request.RawUrl);
 		}
 
+        [Test]
+        public void CanSpecifyRequestAcceptTypes()
+        {
+            builder.AcceptTypes = new[] {"some/type-extension"};
+            var controller = new TestHelperController();
+            builder.InitializeController(controller);
+            Assert.That(controller.HttpContext.Request.AcceptTypes, Is.Not.Null);
+            Assert.That(controller.HttpContext.Request.AcceptTypes.Length, Is.EqualTo(1));
+            Assert.That(controller.HttpContext.Request.AcceptTypes[0], Is.EqualTo("some/type-extension"));
+        }
+
 		[Test]
 		public void When_response_status_is_set_it_should_persist()
 		{