The incorporation of associate members into Opus Dei began in 1950, following the approval of Opus Dei as a secular institute. This study focuses on the formation of the women who had applied for admis-sion as associates in the first half of the 1950s in Spain. These were women with a celibate commitment, who had a professional career and who did not live in Opus Dei centers. Firstly, the methods and content of this personal and collective formation are discussed, and secondly, the response of some of these women is examined.