Pulsar polarimetry is an important tool for the investigation of the physical processes and the environment in the magnetosphere. However, the great variety of observed polarization states and the few obvious systematics hamper a straightforward interpretation. In this paper it is shown that the polarimetric features of pulsars are much more systematic at high radio frequencies. An analysis of 116 profiles at 4.85 GHz reveals a clear correlation between the degree of polarization and Ė. Also evidence is shown for pulsars with a heavily increasing degree of circular polarization. Further, a basic concept of a simple magnetospheric propagation scenario is presented, which can account for a variety of polarimetric properties of pulsars.