In 906, the Abbot Reginon von Prüm issued a questionnaire concerning the sins perpetrated during the past year within a given parish. Two important improvements can be found in the questionnaire as compared to the already existing handbooks of penance: instead of being used for the private confession of sins, it was designed for a public investigation, and it demonstrates an effort toward some objectivity, by avoiding reproofs or value judgements. For these reasons, it appears as a significant advance in survey questionnaires. A French translation of the questionnaire is provided in the appendix.