diff --git a/Octokit/Clients/ReleasesClient.cs b/Octokit/Clients/ReleasesClient.cs
index 1a82f7fdc8..a8fb1958f1 100644
--- a/Octokit/Clients/ReleasesClient.cs
+++ b/Octokit/Clients/ReleasesClient.cs
@@ -1,6 +1,8 @@
 using System.Threading.Tasks;
 using System.Collections.Generic;
 using System.Threading;
+using System.IO;
+using System;
 
 namespace Octokit
 {
@@ -501,6 +503,37 @@ public Task<ReleaseAsset> GetAsset(long repositoryId, int assetId)
             return ApiConnection.Get<ReleaseAsset>(endpoint);
         }
 
+        /// <summary>
+        /// Gets a raw read-only stream containing the file data for the specified asset
+        /// </summary>
+        /// <remarks>
+        /// See the <a href="http://developer.github.com/v3/repos/releases/#get-a-single-release-asset">API documentation</a> for more information.
+        /// </remarks>
+        /// <param name="repositoryId">The Id of the repository</param>
+        /// <param name="assetId">The id of the <see cref="ReleaseAsset"/></param>
+        [ManualRoute("GET", "/repositories/{id}/releases/assets/{asset_id}")]
+        public Task<Stream> DownloadAsset(long repositoryId, int assetId)
+        {
+            var endpoint = ApiUrls.Asset(repositoryId, assetId);
+            return ApiConnection.GetRawStream(endpoint, null, "application/octet-stream");
+        }
+
+        /// <summary>
+        /// Gets a raw read-only stream containing the file data for the specified asset
+        /// </summary>
+        /// <remarks>
+        /// See the <a href="http://developer.github.com/v3/repos/releases/#get-a-single-release-asset">API documentation</a> for more information.
+        /// </remarks>
+        /// <param name="owner">The repository's owner</param>
+        /// <param name="name">The repository's name</param>
+        /// <param name="assetId">The id of the <see cref="ReleaseAsset"/></param>
+        [ManualRoute("GET", "/repositories/{id}/releases/assets/{asset_id}")]
+        public Task<Stream> DownloadAsset(string owner, string name, int assetId)
+        {
+            var endpoint = ApiUrls.Asset(owner, name, assetId);
+            return ApiConnection.GetRawStream(endpoint, null, "application/octet-stream");
+        }
+
         /// <summary>
         /// Edits the <see cref="ReleaseAsset"/> for the specified release of the specified repository.
         /// </summary>
diff --git a/Octokit/Http/ApiConnection.cs b/Octokit/Http/ApiConnection.cs
index 929de72a65..2de304ce42 100644
--- a/Octokit/Http/ApiConnection.cs
+++ b/Octokit/Http/ApiConnection.cs
@@ -125,6 +125,31 @@ public async Task<string> GetHtml(Uri uri, IDictionary<string, string> parameter
             return response.Body;
         }
 
+        /// <summary>
+        /// Gets the raw content of the API resource at the specified URI.
+        /// </summary>
+        /// <param name="uri">URI of the API resource to get</param>
+        /// <param name="accepts">Accept header to use for the API request</param>
+        /// <param name="parameters">Parameters to add to the API request</param>
+        /// <returns>The API resource's raw content or <c>null</c> if the <paramref name="uri"/> points to a directory.</returns>
+        /// <exception cref="ApiException">Thrown when an API error occurs.</exception>
+        public async Task<byte[]> GetRaw(Uri uri, IDictionary<string, string> parameters, string accepts)
+        {
+            Ensure.ArgumentNotNull(uri, nameof(uri));
+
+            var response = await Connection.GetRaw(uri, parameters, accepts).ConfigureAwait(false);
+            return response.Body;
+        }
+
+        /// <inheritdoc/>
+        public async Task<Stream> GetRawStream(Uri uri, IDictionary<string, string> parameters, string accepts)
+        {
+            Ensure.ArgumentNotNull(uri, nameof(uri));
+
+            var response = await Connection.GetRawStream(uri, parameters, accepts).ConfigureAwait(false);
+            return response.Body;
+        }
+
         /// <summary>
         /// Gets the raw content of the API resource at the specified URI.
         /// </summary>
diff --git a/Octokit/Http/Connection.cs b/Octokit/Http/Connection.cs
index 091af09ca9..f5394f990d 100644
--- a/Octokit/Http/Connection.cs
+++ b/Octokit/Http/Connection.cs
@@ -224,6 +224,62 @@ public Task<IApiResponse<string>> GetHtml(Uri uri, IDictionary<string, string> p
             });
         }
 
+        /// <summary>
+        /// Performs an asynchronous HTTP GET request that expects a <seealso cref="IResponse"/> containing raw data.
+        /// </summary>
+        /// <param name="uri">URI endpoint to send request to</param>
+        /// <param name="parameters">Querystring parameters for the request</param>
+        /// <param name="accepts">Accept header to use for the API request</param>
+        /// <returns><seealso cref="IResponse"/> representing the received HTTP response</returns>
+        /// <remarks>The <see cref="IResponse.Body"/> property will be <c>null</c> if the <paramref name="uri"/> points to a directory instead of a file</remarks>
+        public Task<IApiResponse<byte[]>> GetRaw(Uri uri, IDictionary<string, string> parameters, string accepts)
+        {
+            Ensure.ArgumentNotNull(uri, nameof(uri));
+
+            var req = new Request
+            {
+                Method = HttpMethod.Get,
+                BaseAddress = BaseAddress,
+                Endpoint = uri.ApplyParameters(parameters),
+            };
+            req.Headers.Add("Accept", accepts);
+
+            return GetRaw(req);
+        }
+
+        /// <inheritdoc/>
+        public Task<IApiResponse<byte[]>> GetRaw(Uri uri, IDictionary<string, string> parameters, TimeSpan timeout, string accepts)
+        {
+            Ensure.ArgumentNotNull(uri, nameof(uri));
+
+            var req = new Request
+            {
+                Method = HttpMethod.Get,
+                BaseAddress = BaseAddress,
+                Endpoint = uri.ApplyParameters(parameters),
+                Timeout = timeout
+            };
+            req.Headers.Add("Accept", accepts);
+
+            return GetRaw(req);
+        }
+
+        /// <inheritdoc/>
+        public Task<IApiResponse<Stream>> GetRawStream(Uri uri, IDictionary<string, string> parameters, string accepts)
+        {
+            Ensure.ArgumentNotNull(uri, nameof(uri));
+
+            var req = new Request
+            {
+                Method = HttpMethod.Get,
+                BaseAddress = BaseAddress,
+                Endpoint = uri.ApplyParameters(parameters)
+            };
+            req.Headers.Add("Accept", accepts);
+
+            return GetRawStream(req);
+        }
+
         /// <summary>
         /// Performs an asynchronous HTTP GET request that expects a <seealso cref="IResponse"/> containing raw data.
         /// </summary>
@@ -737,14 +793,16 @@ public IResponseCache ResponseCache
 
         async Task<IApiResponse<string>> GetHtml(IRequest request)
         {
-            request.Headers.Add("Accept", AcceptHeaders.StableVersionHtml);
+            if (request.Headers.ContainsKey("Accept") is false)
+                request.Headers.Add("Accept", AcceptHeaders.StableVersionHtml);
             var response = await RunRequest(request, CancellationToken.None).ConfigureAwait(false);
             return new ApiResponse<string>(response, response.Body as string);
         }
 
         async Task<IApiResponse<byte[]>> GetRaw(IRequest request)
         {
-            request.Headers.Add("Accept", AcceptHeaders.RawContentMediaType);
+            if (request.Headers.ContainsKey("Accept") is false)
+                request.Headers.Add("Accept", AcceptHeaders.RawContentMediaType);
             var response = await RunRequest(request, CancellationToken.None).ConfigureAwait(false);
 
             if (response.Body is Stream stream)
@@ -757,7 +815,8 @@ async Task<IApiResponse<byte[]>> GetRaw(IRequest request)
         
         async Task<IApiResponse<Stream>> GetRawStream(IRequest request)
         {
-            request.Headers.Add("Accept", AcceptHeaders.RawContentMediaType);
+            if (request.Headers.ContainsKey("Accept") is false)
+                request.Headers.Add("Accept", AcceptHeaders.RawContentMediaType);
             var response = await RunRequest(request, CancellationToken.None).ConfigureAwait(false);
             
             return new ApiResponse<Stream>(response, response.Body as Stream);
diff --git a/Octokit/Http/IApiConnection.cs b/Octokit/Http/IApiConnection.cs
index 3888f5883a..92180da7c7 100644
--- a/Octokit/Http/IApiConnection.cs
+++ b/Octokit/Http/IApiConnection.cs
@@ -63,6 +63,26 @@ public interface IApiConnection
         /// <exception cref="ApiException">Thrown when an API error occurs.</exception>
         Task<string> GetHtml(Uri uri, IDictionary<string, string> parameters);
 
+        /// <summary>
+        /// Gets the raw content of the API resource at the specified URI.
+        /// </summary>
+        /// <param name="uri">URI of the API resource to get</param>
+        /// <param name="accepts">Accept header to use for the API request</param>
+        /// <param name="parameters">Parameters to add to the API request</param>
+        /// <returns>The API resource's raw content or <c>null</c> if the <paramref name="uri"/> points to a directory.</returns>
+        /// <exception cref="ApiException">Thrown when an API error occurs.</exception>
+        Task<byte[]> GetRaw(Uri uri, IDictionary<string, string> parameters, string accepts);
+
+        /// <summary>
+        /// Gets the raw stream of the API resource at the specified URI.
+        /// </summary>
+        /// <param name="uri">URI of the API resource to get</param>
+        /// <param name="parameters">Parameters to add to the API request</param>
+        /// <param name="accepts">Accept header to use for the API request</param>
+        /// <returns>The API resource's raw stream or <c>null</c> if the <paramref name="uri"/> points to a directory.</returns>
+        /// <exception cref="ApiException">Thrown when an API error occurs.</exception>
+        Task<Stream> GetRawStream(Uri uri, IDictionary<string, string> parameters, string accepts);
+
         /// <summary>
         /// Gets the raw content of the API resource at the specified URI.
         /// </summary>
diff --git a/Octokit/Http/IConnection.cs b/Octokit/Http/IConnection.cs
index 4e75a10975..1041549602 100644
--- a/Octokit/Http/IConnection.cs
+++ b/Octokit/Http/IConnection.cs
@@ -22,6 +22,37 @@ public interface IConnection : IApiInfoProvider
         /// <returns><seealso cref="IResponse"/> representing the received HTTP response</returns>
         Task<IApiResponse<string>> GetHtml(Uri uri, IDictionary<string, string> parameters);
 
+        /// <summary>
+        /// Performs an asynchronous HTTP GET request that expects a <seealso cref="IResponse"/> containing raw data.
+        /// </summary>
+        /// <param name="uri">URI endpoint to send request to</param>
+        /// <param name="parameters">Querystring parameters for the request</param>
+        /// <param name="accepts">Accept header to use for the API request</param>
+        /// <returns><seealso cref="IResponse"/> representing the received HTTP response</returns>
+        /// <remarks>The <see cref="IResponse.Body"/> property will be <c>null</c> if the <paramref name="uri"/> points to a directory instead of a file</remarks>
+        Task<IApiResponse<byte[]>> GetRaw(Uri uri, IDictionary<string, string> parameters, string accepts);
+
+        /// <summary>
+        /// Performs an asynchronous HTTP GET request that expects a <seealso cref="IResponse"/> containing raw data.
+        /// </summary>
+        /// <param name="uri">URI endpoint to send request to</param>
+        /// <param name="parameters">Querystring parameters for the request</param>
+        /// <param name="accepts">Accept header to use for the API request</param>
+        /// <param name="timeout">The Timeout value</param>
+        /// <returns><seealso cref="IResponse"/> representing the received HTTP response</returns>
+        /// <remarks>The <see cref="IResponse.Body"/> property will be <c>null</c> if the <paramref name="uri"/> points to a directory instead of a file</remarks>
+        Task<IApiResponse<byte[]>> GetRaw(Uri uri, IDictionary<string, string> parameters, TimeSpan timeout, string accepts);
+
+        /// <summary>
+        /// Performs an asynchronous HTTP GET request that expects a <seealso cref="IResponse"/> containing raw data.
+        /// </summary>
+        /// <param name="uri">URI endpoint to send request to</param>
+        /// <param name="parameters">Querystring parameters for the request</param>
+        /// <param name="accepts">Accept header to use for the API request</param>
+        /// <returns><seealso cref="IResponse"/> representing the received HTTP response</returns>
+        /// <remarks>The <see cref="IResponse.Body"/> property will be <c>null</c> if the <paramref name="uri"/> points to a directory instead of a file</remarks>
+        Task<IApiResponse<Stream>> GetRawStream(Uri uri, IDictionary<string, string> parameters, string accepts);
+
         /// <summary>
         /// Performs an asynchronous HTTP GET request that expects a <seealso cref="IResponse"/> containing raw data.
         /// </summary>