If you create a class like this: class TestClass { int _myField; public TestClass(int myField) { } } And then hit Alt-Enter on the _myField member and choose "Initialse Field From Constructor Parameter", Resharper changes the constructor to the following: public TestClass(int myField, int myField) { _myField = myField; } Clearly this is not what's intended, and doesn't compile, either. Resharper should skip adding existing constructor parameters and just add the assignment. (Just as a note, if you hit Alt-Enter on the 'myField' constructor parameter and chose 'Initialize field...', then the appropriate code IS generated without any spurious duplication)