Where i work, people (consultants) feel pressed to release features as fast as possible. So instead of spending too much time on thinking about how to do things the right way or because they don't want to break anything, code gets copied from different modules and modified.

It's not easy to prevent this, since the code base is open to the whole company. Lots of people work on this.

Now that the mess is there already, what is the best way to remove those redundancies without breaking too much?