This paper refers to three categories of sources: The 75000 Radio survey which has been the radio audience reference survey in France for more than ten years. The Radio panel-, in 1993 and 1996 Mediametrie conducted a three week radio panel. The diarists were recruited by telephone among recent respondents of the 75000. The sample consisted of 4680 complete diaries in 1993 and 5068 in 1997. The 1993 and 1996 issues included weekend questions about the stations memorized in the household. The third survey, Radio set memorization behaviours is a poll that Mediametrie conducted in April 1997 among 300 persons owning at least one memorized radio set, and who declared having personally memorized the set they use most. This survey was designed to deepen the panels weekend questions relative to memorization. This poll consisted in questions on the following topics: o personal and/or collective usage of the most used radio set, o number of stations memorized on this radio set, o frequency of setting memorization, o personal and collective reasons for selecting stations, o stations memorized on the first button, o awareness and listening frequency of national stations, o listening of non memorized stations.