diff --git a/StackExchange.Profiling.Tests/SqlFormatterTest.cs b/StackExchange.Profiling.Tests/SqlFormatterTest.cs
index a54925bb0..8e5ae7a3d 100644
--- a/StackExchange.Profiling.Tests/SqlFormatterTest.cs
+++ b/StackExchange.Profiling.Tests/SqlFormatterTest.cs
@@ -10,7 +10,9 @@ namespace StackExchange.Profiling.Tests
     [TestFixture]
     public class SqlFormatterTest
     {
-        private SqlServerFormatter _formatter;
+	    private const string None = "";
+	    private const string At = "@";
+	    private SqlServerFormatter _formatter;
         private string _commandText;
         private SqlCommand _dbCommand;
         private static Dictionary<RuntimeTypeHandle, DbType> _dbTypeMap;
@@ -98,7 +100,7 @@ private static DbType GetDbType(Type type)
         }
 
         [Test]
-        public void EnsureVerboseSqlServerFormatterAddsOnlyInformation()
+        public void EnsureVerboseSqlServerFormatterOnlyAddsInformation()
         {
             // arrange
 			// overwrite the formatter
@@ -130,13 +132,13 @@ public void TabelQueryWithoutParameters()
         }
 
         [Test]
-        public void TableQueryWithOneParameters()
+        public void TableQueryWithOneParameters([Values(None, At)] string at)
         {
             // arrange
             _commandText = "select 1 from dbo.Table where x = @a";
             const string expectedOutput = "DECLARE @a int = 123;\r\n\r\nselect 1 from dbo.Table where x = @a;";
             CreateDbCommand(CommandType.Text);
-            AddDbParameter<int>("a", 123);
+            AddDbParameter<int>(at + "a", 123);
 
             // act
             var actualOutput = GenerateOutput();
@@ -146,14 +148,14 @@ public void TableQueryWithOneParameters()
         }
 
         [Test]
-        public void TableQueryWithTwoParameters()
+        public void TableQueryWithTwoParameters([Values(None, At)] string at)
         {
             // arrange
             _commandText = "select 1 from dbo.Table where x = @x, y = @y";
             const string expectedOutput = "DECLARE @x int = 123,\r\n        @y bigint = 123;\r\n\r\nselect 1 from dbo.Table where x = @x, y = @y;";
             CreateDbCommand(CommandType.Text);
-            AddDbParameter<int>("x", 123);
-            AddDbParameter<long>("y", 123);
+            AddDbParameter<int>(at + "x", 123);
+            AddDbParameter<long>(at + "y", 123);
 
             // act
             var actualOutput = GenerateOutput();
@@ -178,13 +180,13 @@ public void StoredProcedureCallWithoutParameters()
         }
 
         [Test]
-        public void StoredProcedureCallWithOneParameter()
+        public void StoredProcedureCallWithOneParameter([Values(None, At)] string at)
         {
             // arrange
             _commandText = "dbo.SOMEPROCEDURE";
             const string expectedOutput = "DECLARE @x int = 123;\r\n\r\nEXEC dbo.SOMEPROCEDURE @x = @x;";
             CreateDbCommand(CommandType.StoredProcedure);
-            AddDbParameter<int>("x", 123, ParameterDirection.Input);
+            AddDbParameter<int>(at + "x", 123, ParameterDirection.Input);
 
             // act
             var actualOutput = GenerateOutput();
@@ -194,14 +196,14 @@ public void StoredProcedureCallWithOneParameter()
         }
 
         [Test]
-        public void StoredProcedureCallWithTwoParameter()
+        public void StoredProcedureCallWithTwoParameter([Values(None, At)] string at)
         {
             // arrange
             _commandText = "dbo.SOMEPROCEDURE";
             const string expectedOutput = "DECLARE @x int = 123,\r\n        @y bigint = 123;\r\n\r\nEXEC dbo.SOMEPROCEDURE @x = @x, @y = @y;";
             CreateDbCommand(CommandType.StoredProcedure);
-            AddDbParameter<int>("x", 123, ParameterDirection.Input);
-            AddDbParameter<long>("y", 123, ParameterDirection.Input);
+            AddDbParameter<int>(at + "x", 123, ParameterDirection.Input);
+            AddDbParameter<long>(at + "y", 123, ParameterDirection.Input);
 
             // act
             var actualOutput = GenerateOutput();
@@ -211,13 +213,13 @@ public void StoredProcedureCallWithTwoParameter()
         }
 
         [Test]
-        public void StoredProcedureCallWithOneReturnParameter()
+        public void StoredProcedureCallWithOneReturnParameter([Values(None, At)] string at)
         {
             // arrange
             _commandText = "dbo.SOMEPROCEDURE";
             const string expectedOutput = "DECLARE @retval int;\r\n\r\nEXEC @retval = dbo.SOMEPROCEDURE;\r\nSELECT @retval AS ReturnValue;";
             CreateDbCommand(CommandType.StoredProcedure);
-            AddDbParameter<int>("retval", null, ParameterDirection.ReturnValue);
+            AddDbParameter<int>(at + "retval", null, ParameterDirection.ReturnValue);
 
             // act
             var actualOutput = GenerateOutput();
@@ -227,14 +229,14 @@ public void StoredProcedureCallWithOneReturnParameter()
         }
 
         [Test]
-        public void StoredProcedureCallWithNormalAndReturnParameter()
+        public void StoredProcedureCallWithNormalAndReturnParameter([Values(None, At)] string at)
         {
             // arrange
             _commandText = "dbo.SOMEPROCEDURE";
             const string expectedOutput = "DECLARE @x int = 123,\r\n        @retval int;\r\n\r\nEXEC @retval = dbo.SOMEPROCEDURE @x = @x;\r\nSELECT @retval AS ReturnValue;";
             CreateDbCommand(CommandType.StoredProcedure);
-            AddDbParameter<int>("x", 123, ParameterDirection.Input);
-            AddDbParameter<int>("retval", null, ParameterDirection.ReturnValue);
+            AddDbParameter<int>(at + "x", 123, ParameterDirection.Input);
+            AddDbParameter<int>(at + "retval", null, ParameterDirection.ReturnValue);
 
             // act
             var actualOutput = GenerateOutput();
@@ -244,14 +246,14 @@ public void StoredProcedureCallWithNormalAndReturnParameter()
         }
 
         [Test]
-        public void StoredProcedureCallWithOneOutputParameter()
+        public void StoredProcedureCallWithOneOutputParameter([Values(None, At)] string at)
         {
             // arrange
             _commandText = "dbo.SOMEPROCEDURE";
             const string expectedOutput = "DECLARE @x int = 123;\r\n\r\nEXEC dbo.SOMEPROCEDURE @x = @x OUTPUT;\r\nSELECT @x AS x;";
             CreateDbCommand(CommandType.StoredProcedure);
             // note: since the sql-OUTPUT parameters can be read within the procedure, we need to support setting the value
-            AddDbParameter<int>("x", 123, ParameterDirection.Output);
+            AddDbParameter<int>(at + "x", 123, ParameterDirection.Output);
 
             // act
             var actualOutput = GenerateOutput();
@@ -261,15 +263,15 @@ public void StoredProcedureCallWithOneOutputParameter()
         }
 
         [Test]
-        public void StoredProcedureCallWithTwoOutputParameter()
+        public void StoredProcedureCallWithTwoOutputParameter([Values(None, At)] string at)
         {
             // arrange
             _commandText = "dbo.SOMEPROCEDURE";
             const string expectedOutput = "DECLARE @x int = 123,\r\n        @y int = 123;\r\n\r\nEXEC dbo.SOMEPROCEDURE @x = @x OUTPUT, @y = @y OUTPUT;\r\nSELECT @x AS x, @y AS y;";
             CreateDbCommand(CommandType.StoredProcedure);
             // note: since the sql-OUTPUT parameters can be read within the procedure, we need to support setting the value
-            AddDbParameter<int>("x", 123, ParameterDirection.Output);
-            AddDbParameter<int>("y", 123, ParameterDirection.Output);
+            AddDbParameter<int>(at + "x", 123, ParameterDirection.Output);
+            AddDbParameter<int>(at + "y", 123, ParameterDirection.Output);
 
             // act
             var actualOutput = GenerateOutput();
@@ -279,15 +281,15 @@ public void StoredProcedureCallWithTwoOutputParameter()
         }
 
         [Test]
-        public void StoredProcedureCallWithOneOutputParameterAndOneReturnParameter()
+        public void StoredProcedureCallWithOneOutputParameterAndOneReturnParameter([Values(None, At)] string at)
         {
             // arrange
             _commandText = "dbo.SOMEPROCEDURE";
-            string expectedOutput = "DECLARE @x int = 123,\r\n        @retval int;\r\n\r\nEXEC @retval = dbo.SOMEPROCEDURE @x = @x OUTPUT;\r\nSELECT @retval AS ReturnValue, @x AS x;";
+            const string expectedOutput = "DECLARE @x int = 123,\r\n        @retval int;\r\n\r\nEXEC @retval = dbo.SOMEPROCEDURE @x = @x OUTPUT;\r\nSELECT @retval AS ReturnValue, @x AS x;";
             CreateDbCommand(CommandType.StoredProcedure);
             // note: since the sql-OUTPUT parameters can be read within the procedure, we need to support setting the value
-            AddDbParameter<int>("x", 123, ParameterDirection.Output);
-            AddDbParameter<int>("retval", null, ParameterDirection.ReturnValue);
+            AddDbParameter<int>(at + "x", 123, ParameterDirection.Output);
+            AddDbParameter<int>(at + "retval", null, ParameterDirection.ReturnValue);
 
             // act
             var actualOutput = GenerateOutput();
@@ -297,14 +299,14 @@ public void StoredProcedureCallWithOneOutputParameterAndOneReturnParameter()
         }
 
         [Test]
-        public void StoredProcedureCallWithInOutputParameter()
+        public void StoredProcedureCallWithInOutputParameter([Values(None, At)] string at)
         {
             // arrange
             _commandText = "dbo.SOMEPROCEDURE";
             const string expectedOutput = "DECLARE @x int = 123;\r\n\r\nEXEC dbo.SOMEPROCEDURE @x = @x OUTPUT;\r\nSELECT @x AS x;";
             CreateDbCommand(CommandType.StoredProcedure);
             // note: since the sql-OUTPUT parameters can be read within the procedure, we need to support setting the value
-            AddDbParameter<int>("x", 123, ParameterDirection.InputOutput);
+            AddDbParameter<int>(at + "x", 123, ParameterDirection.InputOutput);
 
             // act
             var actualOutput = GenerateOutput();
diff --git a/StackExchange.Profiling/SqlFormatters/SqlServerFormatter.cs b/StackExchange.Profiling/SqlFormatters/SqlServerFormatter.cs
index 53b8f6b7a..39165aaf6 100644
--- a/StackExchange.Profiling/SqlFormatters/SqlServerFormatter.cs
+++ b/StackExchange.Profiling/SqlFormatters/SqlServerFormatter.cs
@@ -86,14 +86,24 @@ public virtual string FormatSql(string commandText, List<SqlTimingParameter> par
             return formattedText;
         }
 
-        private void GenerateStoreProcedureCall(string commandText, List<SqlTimingParameter> parameters, StringBuilder buffer)
+		private string EnsureParameterPrefix(string name)
+		{
+			return !name.StartsWith("@") ? "@" + name : name;
+		}
+
+		private string RemoveParameterPrefix(string name)
+		{
+			return name.StartsWith("@") ? name.Substring(1) : name;
+		}
+
+	    private void GenerateStoreProcedureCall(string commandText, List<SqlTimingParameter> parameters, StringBuilder buffer)
         {
             buffer.Append("EXEC ");
 
             SqlTimingParameter returnValueParameter = GetReturnValueParameter(parameters);
             if (returnValueParameter != null)
             {
-                buffer.Append("@").Append(returnValueParameter.Name).Append(" = ");
+                buffer.Append(EnsureParameterPrefix(returnValueParameter.Name)).Append(" = ");
             }
 
             buffer.Append(commandText);
@@ -111,14 +121,13 @@ private void GenerateSelectStatement(StringBuilder buffer, List<SqlTimingParamet
 		    var parametersToSelect = parameters.Where(
 			    x => x.Direction == ParameterDirection.InputOutput.ToString() ||
 			         x.Direction == ParameterDirection.Output.ToString())
-					 .Select(x => x.Name.TrimStart('@'))
-					 .Select(x => "@" + x + " AS " + x)
+					 .Select(x => EnsureParameterPrefix(x.Name) + " AS " + RemoveParameterPrefix(x.Name))
 					 .ToList();
 
 		    var returnValueParameter = parameters.SingleOrDefault(x => x.Direction == ParameterDirection.ReturnValue.ToString());
 			if (returnValueParameter != null)
 			{
-				parametersToSelect.Insert(0, "@" + returnValueParameter.Name + " AS ReturnValue");
+				parametersToSelect.Insert(0, EnsureParameterPrefix(returnValueParameter.Name) + " AS ReturnValue");
 			}
 
 		    if (!parametersToSelect.Any()) return;
@@ -163,7 +172,7 @@ private void GenerateStoredProcedureParameters(StringBuilder buffer, List<SqlTim
                 }
 
                 firstParameter = false;
-                buffer.Append(" @").Append(parameter.Name).Append(" = ").Append("@").Append(parameter.Name);
+                buffer.Append(" ").Append(EnsureParameterPrefix(parameter.Name)).Append(" = ").Append(EnsureParameterPrefix(parameter.Name));
 
                 // Output and InputOutput directions treated equally on the database side.
                 if (parameter.Direction == ParameterDirection.Output.ToString() ||
@@ -215,12 +224,8 @@ protected void GenerateParamText(StringBuilder buffer, List<SqlTimingParameter>
                         resolvedType = resolvedType ?? parameter.DbType;
                     }
 
-                    var niceName = parameter.Name;
-                    if (!niceName.StartsWith("@"))
-                    {
-                        niceName = "@" + niceName;
-                    }
-
+                    var niceName = EnsureParameterPrefix(parameter.Name);
+                    
                     buffer.Append(niceName).Append(" ").Append(resolvedType);
 
                     // return values don't have a value assignment