diff --git a/src/Anywhere.ArcGIS/Operation/Query.cs b/src/Anywhere.ArcGIS/Operation/Query.cs
index 9b06522..aa892d6 100644
--- a/src/Anywhere.ArcGIS/Operation/Query.cs
+++ b/src/Anywhere.ArcGIS/Operation/Query.cs
@@ -217,6 +217,26 @@ public string Time
         /// </summary>
         [DataMember(Name = "resultRecordCount")]
         public int? ResultRecordCount { get; set; }
+
+        /// <summary>
+        ///  The names of the fields to group by for output statistics.
+        /// </summary>
+        [IgnoreDataMember]
+        public List<string> GroupByFields { get; set; }
+
+        /// <summary>
+        /// The list of fields to be included in the group by clause. This list is a comma delimited list of field names.
+        /// </summary>
+        /// <remarks>Default is ''</remarks>
+        [DataMember(Name = "groupByFieldsForStatistics")]
+        public string GroupByFieldsValue { get { return GroupByFields == null || !GroupByFields.Any() ? "" : string.Join(",", GroupByFields); } }
+
+
+        /// <summary>
+        /// The list of output statistics.
+        /// </summary>
+        [DataMember(Name = "outStatistics")]
+        public List<OutputStatistic> OutputStatistics { get; set; }
     }
 
     [DataContract]
@@ -438,4 +458,28 @@ public static class FieldDataTypes
         public const string EsriDouble = "esriFieldTypeDouble";
         public const string EsriDate = "esriFieldTypeDate";
     }
+
+    [DataContract]
+    public class OutputStatistic
+    {
+        [DataMember(Name = "statisticType")]
+        public string StatisticType { get; set; }
+
+        [DataMember(Name = "onStatisticField")]
+        public string OnField { get; set; }
+
+        [DataMember(Name = "outStatisticFieldName")]
+        public string OutField { get; set; }
+    }
+
+    public static class StatisticTypes
+    {
+        public const string Count = "count";
+        public const string Sum = "sum";
+        public const string Min = "min";
+        public const string Max = "max";
+        public const string Average = "avg";
+        public const string StandardDeviation = "stddev";
+        public const string Variance = "var";
+    }
 }
diff --git a/tests/Anywhere.ArcGIS.Test.Integration/ArcGISGatewayTests.cs b/tests/Anywhere.ArcGIS.Test.Integration/ArcGISGatewayTests.cs
index ab3e0b4..882704f 100644
--- a/tests/Anywhere.ArcGIS.Test.Integration/ArcGISGatewayTests.cs
+++ b/tests/Anywhere.ArcGIS.Test.Integration/ArcGISGatewayTests.cs
@@ -829,5 +829,39 @@ public async Task CanDownloadExportMapResponse(string rootUrl, string relativeUr
             Assert.NotNull(result.FullName);
             Assert.True(result.Exists);
         }
+
+        [Fact]
+        public async Task QueryForOutputStatistics()
+        {
+            var gateway = new PortalGateway("http://services.arcgis.com/P3ePLMYs2RVChkJx/ArcGIS");
+            var outStats = new List<OutputStatistic>();
+            outStats.Add(new OutputStatistic()
+            {
+                StatisticType = StatisticTypes.Average,
+                OnField = "MALES",
+                OutField = "AVE_MALES"
+            });
+            outStats.Add(new OutputStatistic()
+            {
+                StatisticType = StatisticTypes.Sum,
+                OnField = "MALES",
+                OutField = "SUM_MALES"
+            });
+            var query = new Query("USA_Major_Cities/FeatureServer/0")
+            {
+                GroupByFields = new List<string>(new string[] { "ST" }),
+                OutputStatistics = outStats
+            };
+            var result = await IntegrationTestFixture.TestPolicy.ExecuteAsync(() =>
+            {
+                return gateway.Query<Point>(query);
+            });
+
+            Assert.NotNull(result);
+            Assert.Null(result.Error);
+            Assert.True(result.Features.Any());
+            Assert.NotNull(result.Fields);
+            Assert.True(result.Fields.Where(x => x.Name == "SUM_MALES").Any());
+        }
     }
 }