diff --git a/MapDataReader.Benchmarks/Program.cs b/MapDataReader.Benchmarks/Program.cs
index d402e0c..bf3afe3 100644
--- a/MapDataReader.Benchmarks/Program.cs
+++ b/MapDataReader.Benchmarks/Program.cs
@@ -93,7 +93,7 @@ public static void Setup()
 		}
 	}
 
-	[GenerateDataReaderMapper]
+	[GenerateDataReaderMapper(AccessModifier = "internal")]
 	public class TestClass
 	{
 		public string String1 { get; set; }
diff --git a/MapDataReader.Tests/TestActualCode.cs b/MapDataReader.Tests/TestActualCode.cs
index 76ccaca..2c71391 100644
--- a/MapDataReader.Tests/TestActualCode.cs
+++ b/MapDataReader.Tests/TestActualCode.cs
@@ -3,6 +3,7 @@
 using System.Data;
 using System.Diagnostics.CodeAnalysis;
 using System.Linq;
+using System.Reflection;
 using System.Text;
 using System.Threading.Tasks;
 
@@ -147,7 +148,7 @@ public void TestStringAssign()
 		}
 
 		[TestMethod]
-		public void TestDatatReader()
+		public void TestDataReader()
 		{
 			//create datatable with test data
 			var dt = new DataTable();
@@ -227,6 +228,24 @@ public void TestWrongProperty()
 			o.SetPropertyByName("Name", 123); //try to assign string prop to int
 			Assert.IsTrue(o.Name == null); //wrong type. should be null
 		}
+
+		[TestMethod]
+		public void TestInternalAccessModifier()
+		{
+			var type = typeof(MapperExtensions);
+			var method = type.GetMethod("ToTestClassInternal", BindingFlags.Static | BindingFlags.NonPublic);
+            
+			Assert.IsNotNull(method, "Expected method 'ToTestClassInternal' to be 'internal'.");
+		}
+
+		[TestMethod]
+		public void TestInternalAccessModifierNamed()
+		{
+			var type = typeof(MapperExtensions);
+			var method = type.GetMethod("ToTestClassInternalNamed", BindingFlags.Static | BindingFlags.NonPublic);
+            
+			Assert.IsNotNull(method, "Expected method 'ToTestClassInternalNamed' to be 'internal'.");
+		}
 	}
 
 	public class BaseClass
@@ -239,5 +258,17 @@ public class ChildClass : BaseClass
 	{
 		public string Name { get; set; }
 	}
+
+	[GenerateDataReaderMapper("internal")]
+	internal class TestClassInternal
+	{
+		public int Id { get; set; }
+	}
+	
+	[GenerateDataReaderMapper(AccessModifier = "internal")]
+	internal class TestClassInternalNamed
+	{
+		public int Id { get; set; }
+	}
 }
 
diff --git a/MapDataReader.Tests/TestGenerator.cs b/MapDataReader.Tests/TestGenerator.cs
index 083790b..8ae70aa 100644
--- a/MapDataReader.Tests/TestGenerator.cs
+++ b/MapDataReader.Tests/TestGenerator.cs
@@ -29,6 +29,29 @@ public class MyClass
 		public decimal Price {get;set;}
 	}
 }
+";
+			var src = GetAndCheckOutputSource(userSource);
+		}
+		
+		[TestMethod]
+		public void TestAccessModifier()
+		{
+			string userSource = @"
+using MapDataReader;
+
+namespace MyCode
+{
+	[GenerateDataReaderMapper(AccessModifier = ""internal"")]
+	public class MyClass
+	{
+		public string Name {get;set;}
+		public int Size {get;set;}
+		public bool Enabled {get;set;}
+		public System.DateTime Created {get;set;}
+		public System.DateTimeOffset Offset {get;set;}
+		public decimal Price {get;set;}
+	}
+}
 ";
 			var src = GetAndCheckOutputSource(userSource);
 		}
diff --git a/MapDataReader/MapperGenerator.cs b/MapDataReader/MapperGenerator.cs
index 07e3b91..6863dee 100644
--- a/MapDataReader/MapperGenerator.cs
+++ b/MapDataReader/MapperGenerator.cs
@@ -11,6 +11,17 @@ namespace MapDataReader
 	[AttributeUsage(AttributeTargets.Class, AllowMultiple = false)]
 	public class GenerateDataReaderMapperAttribute : Attribute
 	{
+		public string AccessModifier { get; set; }
+
+		public GenerateDataReaderMapperAttribute()
+		{
+			AccessModifier = "public";
+		}
+
+		public GenerateDataReaderMapperAttribute(string access = "public")
+		{
+			AccessModifier = access;
+		}
 	}
 
 	[Generator]
@@ -28,6 +39,8 @@ public void Execute(GeneratorExecutionContext context)
 
 				var allProperties = typeNodeSymbol.GetAllSettableProperties();
 
+				var accessModifier = GetAccessModifer(typeNode);
+				
 				var src = $@"
 					// <auto-generated/>
 					#pragma warning disable 8019 //disable 'unnecessary using directive' warning
@@ -40,7 +53,7 @@ namespace MapDataReader
 					{{
 						public static partial class MapperExtensions
 						{{
-							public static void SetPropertyByName(this {typeNodeSymbol.FullName()} target, string name, object value)
+							{accessModifier} static void SetPropertyByName(this {typeNodeSymbol.FullName()} target, string name, object value)
 							{{
 								SetPropertyByUpperName(target, name.ToUpperInvariant(), value);
 							}}
@@ -79,7 +92,7 @@ private static void SetPropertyByUpperName(this {typeNodeSymbol.FullName()} targ
 				{
 					src += $@"
 
-							public static List<{typeNodeSymbol.FullName()}> To{typeNode.Identifier}(this IDataReader dr)
+							{accessModifier} static List<{typeNodeSymbol.FullName()}> To{typeNode.Identifier}(this IDataReader dr)
 							{{
 								var list = new List<{typeNodeSymbol.FullName()}>();
 								
@@ -119,6 +132,44 @@ public void Initialize(GeneratorInitializationContext context)
 		{
 			context.RegisterForSyntaxNotifications(() => new TargetTypeTracker());
 		}
+
+		private string GetAccessModifer(ClassDeclarationSyntax typeNode)
+		{
+			// Retrieve the attribute list
+			var attributeList = typeNode.AttributeLists
+				.SelectMany(al => al.Attributes)
+				.FirstOrDefault(attr => attr.Name.ToString() == "GenerateDataReaderMapper");
+
+			if (attributeList?.ArgumentList == null)
+				return "public";
+			
+			var arguments = attributeList.ArgumentList.Arguments;
+			
+			if (arguments.Count == 0)
+				return "public";
+
+			if (arguments.Count == 1)
+			{
+				var argumentExpr = arguments[0].Expression as LiteralExpressionSyntax;
+				return argumentExpr?.Token.ValueText ?? "public";
+			}
+
+			foreach (var argument in arguments)
+			{
+				// Check if the argument is a named argument
+				if (argument is AttributeArgumentSyntax attributeArgument)
+				{
+					var nameEquals = attributeArgument.NameEquals;
+					if (nameEquals?.Name.Identifier.Text == "AccessModifier")
+					{
+						var argumentExpr = argument.Expression as LiteralExpressionSyntax;
+						return argumentExpr?.Token.ValueText ?? "public";
+					}
+				}
+			}
+			
+			return "public";
+		}
 	}
 
 	internal class TargetTypeTracker : ISyntaxContextReceiver
diff --git a/README.md b/README.md
index ab78f76..21c89e8 100644
--- a/README.md
+++ b/README.md
@@ -49,6 +49,20 @@ Some notes for the above
 * Properly maps `DBNull` to `null`.
 * Complex-type properties may not work.
 
+### Access Modifier: `public` or `internal`
+
+You can now specify the access modifer to be used with the mapping methods. By default, the methods will be `public` for backwards compatability.
+
+For example, to prevent exposure outside your assembly you'd set it to `internal`. This would hide the mapping methods outside your model project:
+
+``` csharp
+[GenerateDataReaderMapper("internal")]
+public class MyClass
+{
+    public int ID { get; set; }
+...
+```
+
 ## Bonus API: `SetPropertyByName`
 
 This package also adds a super fast `SetPropertyByName` extension method generated at compile time for your class.