Primary care and regular track residents in one pediatric program were compared with respect to knowledge, perceived level of competence, and attitudes relative to developmental and behavioral pediatrics from beginning to end of the residency. Measures of knowledge and self-perception of competence showed a common pattern characterized by (1) no differences between primary care and regular track residents on entry into the program, (2) significant progress in both groups over the period of the residency, (3) significantly greater progress by primary care residents. Ratings regarding relevance of developmental and behavioral issues for pediatric practice showed that ratings of relevance were significantly higher at the beginning of the residency among primary care residents and remained higher throughout.