Within the theme colloids and/or polymers at surfaces, we investigate methods through which surfaces can be modified in order to give them a specific function. In our group such methods are being developed to make surfaces hydrophobic or hydrophilic, or to make surfaces to which bacteria and proteins do not adsorb. In recent years coatings were developed that self-replenish after damage. This is possible by using polymer chemistry to incorporate additional semi-mobile chains, opening up many possibilities for a number of applications. It may be that cars have to be washed much less frequently in the future, the lifetime of contact lenses may be extended, or fatty fingerprints on mobile phones could be history.