Marketing Library. How we handle common elements

Hey friends.

Usually we work by creating a separate library of structured elements. As new designs are added we then add back elements to the library. If there are elements which are very similar - they are combined into one.

In our experience it's a very good approach to:
- Make sure there are no 50 different shades of blue or 10 variations of a simple button
- Organize work across few designers or few teams of designers.
- Gives front-enders or people on client side a way to easily compose pages out of the elements and grids
- Front-end guys love the structure and give us cookies for that

What approaches do you use to structure your designs?