diff --git a/src/Postmark.Tests/ClientStatisticsTests.cs b/src/Postmark.Tests/ClientStatisticsTests.cs
index d13671d..bca624c 100644
--- a/src/Postmark.Tests/ClientStatisticsTests.cs
+++ b/src/Postmark.Tests/ClientStatisticsTests.cs
@@ -43,17 +43,19 @@ public async void Client_CanGetOutboundStatisticsOverviewWithTimeWindowOrTagFilt
             var allStatsThroughLastMonth = await Client.GetOutboundOverviewStatsAsync(null, _lastMonth);
             var windowFromLastMonth = await Client.GetOutboundOverviewStatsAsync(null, WindowStartDate, _lastMonth);
             var windowFromLastMonthWithTag = await Client.GetOutboundOverviewStatsAsync("test_tag", WindowStartDate, _lastMonth);
+            var outboundStatsForStream = await Client.GetOutboundOverviewStatsAsync(null, null, null, "test_stream");
 
-            AssertStats(allOutboundStats, allStatsThroughLastMonth, windowFromLastMonth, windowFromLastMonthWithTag, f => f.Sent);
+            AssertStats(allOutboundStats, allStatsThroughLastMonth, windowFromLastMonth, windowFromLastMonthWithTag, outboundStatsForStream, f => f.Sent);
         }
 
         private void AssertStats<T>(
-            T alltimeStats, T allstatsThroughLastMonth, T windowFromLastMonth, T windowFromLastMonthWithTag, Func<T, int> statGetter)
+            T alltimeStats, T allstatsThroughLastMonth, T windowFromLastMonth, T windowFromLastMonthWithTag, T outboundStatsForStream, Func<T, int> statGetter)
         {
             Assert.True(statGetter(alltimeStats) > 0, "Stat should be greater than 0");
             Assert.True(statGetter(allstatsThroughLastMonth) > 0, "All Last Month Stat should be greater than 0");
             Assert.True(statGetter(windowFromLastMonth) > 0, "Window from Last Month Stat should be greater than 0");
             Assert.True(statGetter(windowFromLastMonthWithTag) > 0, "Window from Last Month with Tag Stat should be greater than 0");
+            Assert.True(statGetter(outboundStatsForStream) > 0, "Stat for stream should be greater than 0");
 
             Assert.True(statGetter(alltimeStats) > statGetter(allstatsThroughLastMonth));
             Assert.True(statGetter(allstatsThroughLastMonth) > statGetter(windowFromLastMonth));
@@ -68,8 +70,9 @@ public async void Client_CanGetOutboundStatisticsSentCounts()
             var allStatsThroughLastMonth = await Client.GetOutboundSentCountsAsync(null, _lastMonth);
             var windowFromLastMonth = await Client.GetOutboundSentCountsAsync(null, WindowStartDate, _lastMonth);
             var windowFromLastMonthWithTag = await Client.GetOutboundSentCountsAsync("test_tag", WindowStartDate, _lastMonth);
+            var outboundStatsForStream = await Client.GetOutboundSentCountsAsync(null, null, null, "test_stream");
 
-            AssertStats(allOutboundStats, allStatsThroughLastMonth, windowFromLastMonth, windowFromLastMonthWithTag, f => f.Sent);
+            AssertStats(allOutboundStats, allStatsThroughLastMonth, windowFromLastMonth, windowFromLastMonthWithTag, outboundStatsForStream, f => f.Sent);
 
             Assert.True(allOutboundStats.Days.Count() > 0);
             Assert.Equal(allOutboundStats.Sent, allOutboundStats.Days.Sum(k => k.Sent));
@@ -123,9 +126,10 @@ public async void Client_CanGetOutboundStatisticsClientCounts()
             var allStatsThroughLastMonth = await Client.GetOutboundClientUsageCountsAsync(null, _lastMonth);
             var windowFromLastMonth = await Client.GetOutboundClientUsageCountsAsync(null, WindowStartDate, _lastMonth);
             var windowFromLastMonthWithTag = await Client.GetOutboundClientUsageCountsAsync("test_tag", WindowStartDate, _lastMonth);
+            var outboundStatsForStream = await Client.GetOutboundClientUsageCountsAsync(null, null, null, "test_stream");
 
             AssertStats(allOutboundStats, allStatsThroughLastMonth, windowFromLastMonth,
-                windowFromLastMonthWithTag, f => f.ClientCounts.Sum(k => k.Value));
+                windowFromLastMonthWithTag, outboundStatsForStream, f => f.ClientCounts.Sum(k => k.Value));
 
             Assert.True(allOutboundStats.Days.Count() > 0);
             Assert.Equal(allOutboundStats.ClientCounts.Sum(k => k.Value),
diff --git a/src/Postmark/PostmarkClient.cs b/src/Postmark/PostmarkClient.cs
index 820b42d..5f71666 100644
--- a/src/Postmark/PostmarkClient.cs
+++ b/src/Postmark/PostmarkClient.cs
@@ -334,7 +334,7 @@ public async Task<PostmarkServer> EditServerAsync(String name = null, string col
         /// <param name="toDate"></param>
         /// <returns></returns>
         private IDictionary<string, object>
-           ConstructSentStatsFilter(string tag, DateTime? fromDate, DateTime? toDate)
+           ConstructSentStatsFilter(string tag, DateTime? fromDate, DateTime? toDate, string messageStream)
         {
             var parameters = new Dictionary<string, object>();
             if (!string.IsNullOrWhiteSpace(tag))
@@ -349,6 +349,10 @@ private IDictionary<string, object>
             {
                 parameters["todate"] = toDate.Value.ToString(DATE_FORMAT);
             }
+            if (!string.IsNullOrWhiteSpace(messageStream))
+            {
+                parameters["messagestream"] = messageStream;
+            }
             return parameters;
         }
 
@@ -488,11 +492,12 @@ public async Task<PostmarkClicksList> GetClickEventsForMessageAsync(
         /// <param name="tag"></param>
         /// <param name="fromDate"></param>
         /// <param name="toDate"></param>
+        /// <param name="messageStream"></param>
         /// <returns></returns>
         public async Task<PostmarkOutboundOverviewStats> GetOutboundOverviewStatsAsync(
-            string tag = null, DateTime? fromDate = null, DateTime? toDate = null)
+            string tag = null, DateTime? fromDate = null, DateTime? toDate = null, string messageStream = null)
         {
-            var parameters = ConstructSentStatsFilter(tag, fromDate, toDate);
+            var parameters = ConstructSentStatsFilter(tag, fromDate, toDate, messageStream);
             return await this.ProcessNoBodyRequestAsync<PostmarkOutboundOverviewStats>
                 ("/stats/outbound", parameters);
         }
@@ -503,11 +508,12 @@ public async Task<PostmarkOutboundOverviewStats> GetOutboundOverviewStatsAsync(
         /// <param name="tag"></param>
         /// <param name="fromDate"></param>
         /// <param name="toDate"></param>
+        /// <param name="messageStream"></param>
         /// <returns></returns>
         public async Task<PostmarkOutboundSentStats>
-            GetOutboundSentCountsAsync(string tag = null, DateTime? fromDate = null, DateTime? toDate = null)
+            GetOutboundSentCountsAsync(string tag = null, DateTime? fromDate = null, DateTime? toDate = null, string messageStream = null)
         {
-            var parameters = ConstructSentStatsFilter(tag, fromDate, toDate);
+            var parameters = ConstructSentStatsFilter(tag, fromDate, toDate, messageStream);
             return await this.ProcessNoBodyRequestAsync<PostmarkOutboundSentStats>
                 ("/stats/outbound/sends", parameters);
         }
@@ -518,11 +524,12 @@ public async Task<PostmarkOutboundSentStats>
         /// <param name="tag"></param>
         /// <param name="fromDate"></param>
         /// <param name="toDate"></param>
+        /// <param name="messageStream"></param>
         /// <returns></returns>
         public async Task<PostmarkOutboundBounceStats>
-            GetOutboundBounceCountsAsync(string tag = null, DateTime? fromDate = null, DateTime? toDate = null)
+            GetOutboundBounceCountsAsync(string tag = null, DateTime? fromDate = null, DateTime? toDate = null, string messageStream = null)
         {
-            var parameters = ConstructSentStatsFilter(tag, fromDate, toDate);
+            var parameters = ConstructSentStatsFilter(tag, fromDate, toDate, messageStream);
             return await this.ProcessNoBodyRequestAsync<PostmarkOutboundBounceStats>
                 ("/stats/outbound/bounces", parameters);
         }
@@ -533,10 +540,11 @@ public async Task<PostmarkOutboundBounceStats>
         /// <param name="tag"></param>
         /// <param name="fromDate"></param>
         /// <param name="toDate"></param>
+        /// <param name="messageStream"></param>
         /// <returns></returns>
-        public async Task<PostmarkOutboundSpamComplaintStats> GetOutboundSpamComplaintCountsAsync(string tag = null, DateTime? fromDate = null, DateTime? toDate = null)
+        public async Task<PostmarkOutboundSpamComplaintStats> GetOutboundSpamComplaintCountsAsync(string tag = null, DateTime? fromDate = null, DateTime? toDate = null, string messageStream = null)
         {
-            var parameters = ConstructSentStatsFilter(tag, fromDate, toDate);
+            var parameters = ConstructSentStatsFilter(tag, fromDate, toDate, messageStream);
             return await this.ProcessNoBodyRequestAsync<PostmarkOutboundSpamComplaintStats>
                 ("/stats/outbound/spam", parameters);
         }
@@ -547,10 +555,11 @@ public async Task<PostmarkOutboundSpamComplaintStats> GetOutboundSpamComplaintCo
         /// <param name="tag"></param>
         /// <param name="fromDate"></param>
         /// <param name="toDate"></param>
+        /// <param name="messageStream"></param>
         /// <returns></returns>
-        public async Task<PostmarkOutboundTrackedStats> GetOutboundTrackingCountsAsync(string tag = null, DateTime? fromDate = null, DateTime? toDate = null)
+        public async Task<PostmarkOutboundTrackedStats> GetOutboundTrackingCountsAsync(string tag = null, DateTime? fromDate = null, DateTime? toDate = null, string messageStream = null)
         {
-            var parameters = ConstructSentStatsFilter(tag, fromDate, toDate);
+            var parameters = ConstructSentStatsFilter(tag, fromDate, toDate, messageStream);
             return await this.ProcessNoBodyRequestAsync<PostmarkOutboundTrackedStats>
                 ("/stats/outbound/tracked", parameters);
         }
@@ -561,10 +570,11 @@ public async Task<PostmarkOutboundTrackedStats> GetOutboundTrackingCountsAsync(s
         /// <param name="tag"></param>
         /// <param name="fromDate"></param>
         /// <param name="toDate"></param>
+        /// <param name="messageStream"></param>
         /// <returns></returns>
-        public async Task<PostmarkOutboundOpenStats> GetOutboundOpenCountsAsync(string tag = null, DateTime? fromDate = null, DateTime? toDate = null)
+        public async Task<PostmarkOutboundOpenStats> GetOutboundOpenCountsAsync(string tag = null, DateTime? fromDate = null, DateTime? toDate = null, string messageStream = null)
         {
-            var parameters = ConstructSentStatsFilter(tag, fromDate, toDate);
+            var parameters = ConstructSentStatsFilter(tag, fromDate, toDate, messageStream);
             return await this.ProcessNoBodyRequestAsync<PostmarkOutboundOpenStats>
                 ("/stats/outbound/opens", parameters);
         }
@@ -575,10 +585,11 @@ public async Task<PostmarkOutboundOpenStats> GetOutboundOpenCountsAsync(string t
         /// <param name="tag"></param>
         /// <param name="fromDate"></param>
         /// <param name="toDate"></param>
+        /// <param name="messageStream"></param>
         /// <returns></returns>
-        public async Task<PostmarkOutboundPlatformStats> GetOutboundPlatformCountsAsync(string tag = null, DateTime? fromDate = null, DateTime? toDate = null)
+        public async Task<PostmarkOutboundPlatformStats> GetOutboundPlatformCountsAsync(string tag = null, DateTime? fromDate = null, DateTime? toDate = null, string messageStream = null)
         {
-            var parameters = ConstructSentStatsFilter(tag, fromDate, toDate);
+            var parameters = ConstructSentStatsFilter(tag, fromDate, toDate, messageStream);
             return await this.ProcessNoBodyRequestAsync<PostmarkOutboundPlatformStats>
                 ("/stats/outbound/opens/platforms", parameters);
         }
@@ -589,10 +600,11 @@ public async Task<PostmarkOutboundPlatformStats> GetOutboundPlatformCountsAsync(
         /// <param name="tag"></param>
         /// <param name="fromDate"></param>
         /// <param name="toDate"></param>
+        /// <param name="messageStream"></param>
         /// <returns></returns>
-        public async Task<PostmarkOutboundClientStats> GetOutboundClientUsageCountsAsync(string tag = null, DateTime? fromDate = null, DateTime? toDate = null)
+        public async Task<PostmarkOutboundClientStats> GetOutboundClientUsageCountsAsync(string tag = null, DateTime? fromDate = null, DateTime? toDate = null, string messageStream = null)
         {
-            var parameters = ConstructSentStatsFilter(tag, fromDate, toDate);
+            var parameters = ConstructSentStatsFilter(tag, fromDate, toDate, messageStream);
             var result = await this.ProcessNoBodyRequestAsync<Dictionary<string, object>>("/stats/outbound/opens/emailclients", parameters);
 
             var retval = new PostmarkOutboundClientStats();
@@ -637,9 +649,9 @@ public async Task<PostmarkOutboundClientStats> GetOutboundClientUsageCountsAsync
         /// <param name="fromDate"></param>
         /// <param name="toDate"></param>
         /// <returns></returns>
-        public async Task<PostmarkOutboundReadStats> GetOutboundReadtimeStatsAsync(string tag = null, DateTime? fromDate = null, DateTime? toDate = null)
+        public async Task<PostmarkOutboundReadStats> GetOutboundReadtimeStatsAsync(string tag = null, DateTime? fromDate = null, DateTime? toDate = null, string messageStream = null)
         {
-            var parameters = ConstructSentStatsFilter(tag, fromDate, toDate);
+            var parameters = ConstructSentStatsFilter(tag, fromDate, toDate, messageStream);
             var result = await this.ProcessNoBodyRequestAsync<Dictionary<string, object>>("/stats/outbound/opens/readtimes", parameters);
 
             var retval = new PostmarkOutboundReadStats();