The purpose of this study was to examine how perceived attitudinal similarity (measured as similarity in general outlook, values, and problem-solving approach) and demographic similarity operationalized as similarity in race and gender, affected protégés' support and satisfaction from their informal mentoring relationships. Scandura and Katerberg's (1988) 3-factor scale of mentor functions was used to measure vocational, psychosocial, and role-modeling support. Participants were 144 protégés from diverse backgrounds (54% female; 54% non-White). Perceived attitudinal similarity was a better predictor of protégés' satisfaction with and support received from their mentors than was demographic similarity.