The mentor relationship is increasingly being seen as an important ingredient in career development, particularly for women managers and professionals. This study examined sex differences and cross-sex effects of the mentor-protege relationship. Data were collected, using questionnaires, from 81 male and 13 female mentors in high technology firms. Both sex and cross-sex effects were observed. Psychosocial functions were more prevalent when women were involved as either mentors or proteges and most prevalent in pairs of women.