Write better code is a must, and the easiest test for whether there's any appetite for improvement. if there is, their changes to your better code will be less bad than the changes to the other stuff. If they plough on and throw equally bad code all over your changes (or even refactor your stuff to their idea of 'good'), they probably won't ever agree with you. Not so sure about comments - too easy to come across as a lecture, given the usual problems conveying tone in writing. If you've done something non-obvious, then sure, leave a brief note explaining the improvement. But the main thing is to try to work out what's in it for the people you're trying to convince. How does it benefit them? Unless you're in a management position, you have to show them how it makes *their* job easier, overall. And yeah, if they just don't get it, polish your CV.