Polymers are subject to different ageing mechanisms, which often occur in combination. A distinction is made between mechanical, chemical, thermal, biological and radiation-induced ageing. The resulting degradation can be intentional, e.g. in the case of degradable or resorbable biomaterials. The aim here is to adapt the rate of degradation to the ambient environment by influencing the material. However, degradation can also occur undesirably and is controlled by the physiological parameters. This can be mechanical abrasion (abrasion, tribology), but also chemical and even biological degradation through exposure of the biomaterial to body fluids, tissues or microorganisms (oxidation/hydrolysis/enzymatically catalyzed hydrolysis). Polymer degradation can be simulated experimentally in vitro and results in statements on mechanical, physicochemical and morphological ageing. We investigate unfilled and highly filled polymers and their areas of application in biomedical engineering. From this, new strategies for material synthesis can be derived.