The author describes how four medical librarians influenced his career and his values. Louise Darling, Brad Rogers, Estelle Brodman, and Bernice Hetzner became a professional extended family, each one contributing to different aspects of his career path, socialization to the profession, priorities, and principles of management. The lessons they imparted directly and by example are followed through the development of the author's career. Although the norms of the profession are different today, there remains a place for mentors.