Questions about the necessity of tutors' content experience and what skills are required to make tutor behavior effective have received increased attention in the literature about problem-based learning. The present study attempts to examine the effects of context-specific variables through analysis of the generalizability of tutor behavior and the relationship between organizational background and tutoring. Subjects were 427 members of the academic staff of a Dutch medical school. Data were gathered about 2,299 tutorials over 8 consecutive years, with staff members guiding approximately 2 to 4 tutorials each year. Two studies were conducted, one to determine the stability of tutor behavior across different discussion groups; the other to explore influences on tutoring of departmental background. Results of the first study indicate that stability and generalizability of tutor behavior is low over multiple time points. Correlations between two consecutive tutorials were approximately 0.20. The second study shows that tutor behavior is related to departmental background. It is concluded that what a tutor does in a discussion group depends on context-specific characteristics and on organizational background, both features that should be considered in future research. Four tables are included. (Contains 17 references.) (Author/SLD)