Successful higher education faculty, those who get promoted and tenured, who get recognized for contributions, who produce more and significant research, frequently consult colleagues. This article summarizes what is known about colleague relationships with the hope of stimulating further research to extend current conclusions to medical school faculty. In the spring of 1992, a systematic literature review was conducted using database searches and author review of 137 selected books and articles using a standard protocol; preference was given to articles that were data-oriented, used quality designs, and related directly to the topic. Forty-seven "best" sources, published between 1963 and 1991, were included in the review of (1) types and configurations of colleague relationships, (2) forming and maintaining colleague relationships, (3) colleague effects on faculty success, (4) functions of colleague relationships, (5) changes in colleague relationships over a career, and (6) effects on methods, size, and configuration of colleague relationships. Among the conclusions reached are that (1) there are a variety of types or configurations of colleague relationships, all with different functions and effects on faculty performance; (2) dyadic conceptions of colleague relationships are insufficient to explain the functions of colleague relationships; and (3) the most important source for developing colleague relationships is professional associations, while the least important source is one's own institution.