That advertising on the radio works was already proven for Germany in general terms in 1994 with the basic study Qualitaten der Radiowerbung I (Qualities of Radio Advertising I). To be able to answer questions beyond the general proof of effectiveness of radio as an advertising Medium the radio marketers ARD-Werbung Sales & Services IP Multimedia Deutschland and Radio Marketing Service (RMS) commissioned a second study in 1996. With its longer study period of one year and resulting greater number of cases and campaigns observed it became possible to provide more detailed impact analyses. The impact achieved at different stages of radio campaigns the optimum number of contacts for these campaigns and the positive contribution of radio towards mixed campaigns are just some of the issues covered. The results on hand make radio more transparent and show that spending radio is worthwhile. Radio can both be used extremely effectively as a Principal medium and can contribute importantly to the advertising effect °f combined radio/TV campaigns.