diff --git a/WebApiThrottle.WebApiDemo/Helpers/CustomThrottlingHandler.cs b/WebApiThrottle.WebApiDemo/Helpers/CustomThrottlingHandler.cs
index 0522dfe..6130fba 100644
--- a/WebApiThrottle.WebApiDemo/Helpers/CustomThrottlingHandler.cs
+++ b/WebApiThrottle.WebApiDemo/Helpers/CustomThrottlingHandler.cs
@@ -1,20 +1,21 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using System.Threading.Tasks;
 using System.Web;
 
 namespace WebApiThrottle.WebApiDemo.Helpers
 {
     public class CustomThrottlingHandler : ThrottlingHandler
     {
-        protected override RequestIdentity SetIdentity(System.Net.Http.HttpRequestMessage request)
+        protected override Task<RequestIdentity> SetIdentityAsync(System.Net.Http.HttpRequestMessage request)
         {
-            return new RequestIdentity()
+            return Task.FromResult(new RequestIdentity()
             {
                 ClientKey = request.Headers.Contains("Authorization-Key") ? request.Headers.GetValues("Authorization-Key").First() : "anon",
                 ClientIp = base.GetClientIp(request).ToString(),
                 Endpoint = request.RequestUri.AbsolutePath.ToLowerInvariant()
-            };
+            });
         }
     }
 }
\ No newline at end of file
diff --git a/WebApiThrottle/ThrottlingFilter.cs b/WebApiThrottle/ThrottlingFilter.cs
index 7f1a93c..1b6faf7 100644
--- a/WebApiThrottle/ThrottlingFilter.cs
+++ b/WebApiThrottle/ThrottlingFilter.cs
@@ -129,7 +129,7 @@ public ThrottlePolicy Policy
         /// </summary>
         public HttpStatusCode QuotaExceededResponseCode { get; set; }
 
-        public override void OnActionExecuting(HttpActionContext actionContext)
+        public override async Task OnActionExecutingAsync(HttpActionContext actionContext, System.Threading.CancellationToken cancellationToken)
         {
             EnableThrottlingAttribute attrPolicy = null;
             var applyThrottling = ApplyThrottling(actionContext, out attrPolicy);
@@ -145,7 +145,7 @@ public override void OnActionExecuting(HttpActionContext actionContext)
                 core.Repository = Repository;
                 core.Policy = Policy;
 
-                var identity = SetIdentity(actionContext.Request);
+                var identity = await SetIdentityAsync(actionContext.Request);
 
                 if (!core.IsWhitelisted(identity))
                 {
@@ -219,17 +219,24 @@ public override void OnActionExecuting(HttpActionContext actionContext)
                 }
             }
 
-            base.OnActionExecuting(actionContext);
+            await base.OnActionExecutingAsync(actionContext, cancellationToken);
         }
 
+
+        [Obsolete("This method is deprecated, use SetIdentityAsync instead")]
         protected virtual RequestIdentity SetIdentity(HttpRequestMessage request)
+        {
+            throw new NotImplementedException("This method is deprecated, use SetIdentityAsync instead");
+        }
+
+        protected virtual Task<RequestIdentity> SetIdentityAsync(HttpRequestMessage request)
         {
             var entry = new RequestIdentity();
             entry.ClientIp = core.GetClientIp(request).ToString();
             entry.Endpoint = request.RequestUri.AbsolutePath.ToLowerInvariant();
             entry.ClientKey = request.Headers.Contains("Authorization-Token") ? request.Headers.GetValues("Authorization-Token").First() : "anon";
 
-            return entry;
+            return Task.FromResult(entry);
         }
 
         protected virtual string ComputeThrottleKey(RequestIdentity requestIdentity, RateLimitPeriod period)
diff --git a/WebApiThrottle/ThrottlingHandler.cs b/WebApiThrottle/ThrottlingHandler.cs
index 7bdcd40..0b05509 100644
--- a/WebApiThrottle/ThrottlingHandler.cs
+++ b/WebApiThrottle/ThrottlingHandler.cs
@@ -129,7 +129,7 @@ public ThrottlePolicy Policy
         /// </summary>
         public HttpStatusCode QuotaExceededResponseCode { get; set; }
 
-        protected override Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
+        protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
         {
             // get policy from repo
             if (policyRepository != null)
@@ -139,17 +139,17 @@ protected override Task<HttpResponseMessage> SendAsync(HttpRequestMessage reques
 
             if (policy == null || (!policy.IpThrottling && !policy.ClientThrottling && !policy.EndpointThrottling))
             {
-                return base.SendAsync(request, cancellationToken);
+                return await base.SendAsync(request, cancellationToken);
             }
 
             core.Repository = Repository;
             core.Policy = policy;
 
-            var identity = SetIdentity(request);
+            var identity = await SetIdentityAsync(request);
 
             if (core.IsWhitelisted(identity))
             {
-                return base.SendAsync(request, cancellationToken);
+                return await base.SendAsync(request, cancellationToken);
             }
 
             TimeSpan timeSpan = TimeSpan.FromSeconds(1);
@@ -204,7 +204,7 @@ protected override Task<HttpResponseMessage> SendAsync(HttpRequestMessage reques
                             : string.Format(message, rateLimit, rateLimitPeriod);
 
                         // break execution
-                        return QuotaExceededResponse(
+                        return await QuotaExceededResponse(
                             request,
                             content,
                             QuotaExceededResponseCode,
@@ -214,7 +214,7 @@ protected override Task<HttpResponseMessage> SendAsync(HttpRequestMessage reques
             }
 
             // no throttling required
-            return base.SendAsync(request, cancellationToken);
+            return await base.SendAsync(request, cancellationToken);
         }
 
         protected IPAddress GetClientIp(HttpRequestMessage request)
@@ -222,7 +222,13 @@ protected IPAddress GetClientIp(HttpRequestMessage request)
             return core.GetClientIp(request);
         }
 
+        [Obsolete("This method is deprecated, use SetIdentityAsync instead")]
         protected virtual RequestIdentity SetIdentity(HttpRequestMessage request)
+        {
+            throw new NotImplementedException("This method is deprecated, use SetIdentityAsync instead");
+        }
+
+        protected virtual Task<RequestIdentity> SetIdentityAsync(HttpRequestMessage request)
         {
             var entry = new RequestIdentity();
             entry.ClientIp = core.GetClientIp(request).ToString();
@@ -231,7 +237,7 @@ protected virtual RequestIdentity SetIdentity(HttpRequestMessage request)
                 ? request.Headers.GetValues("Authorization-Token").First() 
                 : "anon";
 
-            return entry;
+            return Task.FromResult(entry);
         }
 
         protected virtual string ComputeThrottleKey(RequestIdentity requestIdentity, RateLimitPeriod period)
diff --git a/WebApiThrottle/ThrottlingMiddleware.cs b/WebApiThrottle/ThrottlingMiddleware.cs
index a9be672..06ec480 100644
--- a/WebApiThrottle/ThrottlingMiddleware.cs
+++ b/WebApiThrottle/ThrottlingMiddleware.cs
@@ -140,7 +140,7 @@ public override async Task Invoke(IOwinContext context)
             core.Repository = Repository;
             core.Policy = policy;
 
-            var identity = SetIdentity(request);
+            var identity = await SetIdentityAsync(request);
 
             if (core.IsWhitelisted(identity))
             {
@@ -213,7 +213,13 @@ public override async Task Invoke(IOwinContext context)
             await Next.Invoke(context);
         }
 
+        [Obsolete("This method is deprecated, use SetIdentityAsync instead")]
         protected virtual RequestIdentity SetIdentity(IOwinRequest request)
+        {
+            throw new NotImplementedException("This method is deprecated, use SetIdentityAsync instead");
+        }
+
+        protected virtual Task<RequestIdentity> SetIdentityAsync(IOwinRequest request)
         {
             var entry = new RequestIdentity();
             entry.ClientIp = request.RemoteIpAddress;
@@ -222,7 +228,7 @@ protected virtual RequestIdentity SetIdentity(IOwinRequest request)
                 ? request.Headers.GetValues("Authorization-Token").First()
                 : "anon";
 
-            return entry;
+            return Task.FromResult(entry);
         }
 
         protected virtual string ComputeThrottleKey(RequestIdentity requestIdentity, RateLimitPeriod period)