For most biomedical applications of polymers biocompatible surface properties are highly needed. here we present various methods to immobilize biocompatible and also bioactive hydrogels on polymer surfaces. In one approach, macroinitiator-based reactive layers are attached to polycondensates which are able to allow the grafting-from of various hydrogels. on the other hand, it is possible to immobilize hydrophilic polymers on various substrates by plasma and e-beam treatment. Stability, swelling and biocompatibility of the polymer films could be verified. by incorporating ph and thermo-responsive groups, it is possible additionally to control the swelling behaviour by external triggers.