This article examines two questions of research. Can we make educational vocational information sessions effective by applying commitment theory (Kiesler, 1971) to this particular aspect of career counseling? Does commitment as part of an initial low-cost behavior (taking part in an information session) have a direct effect or is the effect a mediate one? Data gathered during an experiment involving six sixth-year secondary school classes would appear to suggest that there is a mediate process. To be more precise, the accepted impact of commitment upon the effectiveness of information sessions (post-session information and orientation is more actively sought) would seem to he linked to its mediation by perceived self-efficacy (Bandura, 1997/2003) in orientation. On the other hand, it is not mediated by the behavioral intention (Fishbein, 1980) to take such steps, this being an intention upon which commitment has no effect. The discussion links these results to some of Kiesler's initial questions (commitment as a process of internal self-attribution), and also places them within the framework (proper to counseling) of factors common to all intervention theories and techniques designed to explain the effectiveness of said interventions. (Contains 1 figure and 2 notes.)