On 19 September 1997, Richard Wiegandt celebrated his 65th birthday. As can be seen from his impressive list of publications, he is one of the most active algebraists of the last forty years working mostly in ring theory and related topics. The present note, which is an extended version of an invited talk given at the ICOR 97, is intended to show up some highlights in Richard Wiegandt's development in radical theory, one of his main points of interest. It is thus far away from presenting a complete overview of Wiegandt's scientific work. Some emphasis is given to his older papers, maybe less known to the actual radical community.