This article introduces the concept of men's unmet need for family planning and explains its programmatic relevance. Using data from Demographic and Health Surveys (DHS) of Ghana (1988, 1993) and Kenya (1989, 1993), married men are found to have high levels of unmet need for family planning that are comparable to, although slightly lower than, those for women. The importance of men's unmet need is demonstrated when the analysis is restricted to marital pairs in the DHS samples; trends in the joint unmet need of husbands and wives are shown to be closely associated with the nature of the fertility transitions occurring in Ghana and Kenya. Because of wide discrepancies found between husbands' and wives' unmet need statuses, family planning programs that foster spousal communication are likely to facilitate the transition to lower fertility.