diff --git a/MakeInterface.Demo/Models/Class2.cs b/MakeInterface.Demo/Models/Class2.cs
index 842c11e..fe67f2d 100644
--- a/MakeInterface.Demo/Models/Class2.cs
+++ b/MakeInterface.Demo/Models/Class2.cs
@@ -7,4 +7,8 @@ namespace MakeInterface.Demo.Models;
 public class Class2 : IClass2
 {
     public IClass1? Class1 { get; }
+
+    public string Name { get; set; }
+
+    public string FullName() => $"{Name} {Name}";
 }
diff --git a/MakeInterface.Generator/Extensions/MemberDeclarationSyntaxExtensions.cs b/MakeInterface.Generator/Extensions/MemberDeclarationSyntaxExtensions.cs
index 0224cc8..92ab89a 100644
--- a/MakeInterface.Generator/Extensions/MemberDeclarationSyntaxExtensions.cs
+++ b/MakeInterface.Generator/Extensions/MemberDeclarationSyntaxExtensions.cs
@@ -4,14 +4,14 @@
 namespace MakeInterface.Generator.Extensions;
 internal static class MemberDeclarationSyntaxExtensions
 {
-    public static string GetName(this MemberDeclarationSyntax syntax)
+    public static string? GetName(this MemberDeclarationSyntax syntax)
     {
         return syntax switch
         {
             PropertyDeclarationSyntax property => property.Identifier.Text,
             MethodDeclarationSyntax method => method.Identifier.Text,
             FieldDeclarationSyntax field => field.Declaration.Variables.First().Identifier.Text,
-            _ => throw new NotImplementedException($"Syntax of kind {syntax.GetType().Name} is not implemented"),
+            _ => null
         };
     }
 }
diff --git a/MakeInterface.Generator/InterfaceGenerator.cs b/MakeInterface.Generator/InterfaceGenerator.cs
index 86da192..28dc4ae 100644
--- a/MakeInterface.Generator/InterfaceGenerator.cs
+++ b/MakeInterface.Generator/InterfaceGenerator.cs
@@ -127,10 +127,10 @@ private void Generate(SourceProductionContext ctx, (SemanticModel, CompilationUn
                 continue;
 
             var name = memberSyntax.GetName();
-            if (excludedMembers.Contains(name))
+            if (name is null || excludedMembers.Contains(name))
                 continue;
 
-            if (membersFromImplementedTypes.Contains(memberSyntax.GetName()))
+            if (membersFromImplementedTypes.Contains(name))
                 continue;
 
             var publicModifier = memberSyntax.Modifiers.FirstOrDefault(x => x.IsKind(SyntaxKind.PublicKeyword));
@@ -165,6 +165,7 @@ private void Generate(SourceProductionContext ctx, (SemanticModel, CompilationUn
 
                 var newMethod = methodSyntax
                     .WithBody(null)
+                    .WithExpressionBody(null)
                     .WithSemicolonToken(SyntaxFactory.Token(SyntaxKind.SemicolonToken))
                     .WithModifiers(modifiers);
 
@@ -329,7 +330,7 @@ private InterfaceDeclarationSyntax AddInterfaces(InterfaceDeclarationSyntax inte
 
             // Get members that matches interfaceMembers
             var membersToRemove = interfaceDeclaration.Members
-                .Where(member => baseInterfaceMembers.Contains(member.GetName()))
+                .Where(member => member.GetName() is { } name && baseInterfaceMembers.Contains(name))
                 .ToList();
 
             // Remove the members from the interface declaration.
diff --git a/MakeInterface.Generator/MakeInterface.Generator.csproj b/MakeInterface.Generator/MakeInterface.Generator.csproj
index 1853d82..650d887 100644
--- a/MakeInterface.Generator/MakeInterface.Generator.csproj
+++ b/MakeInterface.Generator/MakeInterface.Generator.csproj
@@ -12,7 +12,7 @@
 		<OutputType>library</OutputType>
 		<TargetFramework>netstandard2.0</TargetFramework>
 		<PackageId>MakeInterface.Generator</PackageId>
-		<Version>0.4.0</Version>
+		<Version>0.4.1</Version>
 		<Authors>Frederik Tegnander</Authors>
 		<Company>COWI</Company>
 		<PackageTags>Interfaces;SourceGenerator;MakeInterface</PackageTags>
diff --git a/MakeInterface.Tests/InterfaceGeneratorTests.cs b/MakeInterface.Tests/InterfaceGeneratorTests.cs
index a1fd4f5..96517c6 100644
--- a/MakeInterface.Tests/InterfaceGeneratorTests.cs
+++ b/MakeInterface.Tests/InterfaceGeneratorTests.cs
@@ -298,6 +298,23 @@ public string Get2()
         }
     }
 }
+""";
+
+        return TestHelper.Verify(source);
+    }
+
+    [Fact]
+    public Task Method_Expression_Body()
+    {
+        var source = """
+namespace MakeInterface.Tests
+{
+    [GenerateInterface]
+    public class Class
+    {
+        public string Get() => return "foo";
+    }
+}
 """;
 
         return TestHelper.Verify(source);
diff --git a/MakeInterface.Tests/Snapshots/InterfaceGeneratorTests.Method_Expression_Body#ITest.g.received.cs b/MakeInterface.Tests/Snapshots/InterfaceGeneratorTests.Method_Expression_Body#ITest.g.received.cs
new file mode 100644
index 0000000..5de0cd4
--- /dev/null
+++ b/MakeInterface.Tests/Snapshots/InterfaceGeneratorTests.Method_Expression_Body#ITest.g.received.cs
@@ -0,0 +1,11 @@
+//HintName: ITest.g.cs
+// <auto-generated/>
+#pragma warning disable
+#nullable enable
+namespace MakeInterface.Tests
+{
+    public partial interface IClass
+    {
+        string Get() => ;
+    }
+}
\ No newline at end of file
diff --git a/MakeInterface.Tests/Snapshots/InterfaceGeneratorTests.Method_Expression_Body#ITest.g.verified.cs b/MakeInterface.Tests/Snapshots/InterfaceGeneratorTests.Method_Expression_Body#ITest.g.verified.cs
new file mode 100644
index 0000000..bee8736
--- /dev/null
+++ b/MakeInterface.Tests/Snapshots/InterfaceGeneratorTests.Method_Expression_Body#ITest.g.verified.cs
@@ -0,0 +1,11 @@
+//HintName: ITest.g.cs
+// <auto-generated/>
+#pragma warning disable
+#nullable enable
+namespace MakeInterface.Tests
+{
+    public partial interface IClass
+    {
+        string Get();
+    }
+}
\ No newline at end of file