A complex relationship exists between population growth and economic development. The historical quantitative evidence is also ambiguous. Many social scientists consider rapid population growth in developing countries to be a major obstacle to development. There are, however, many ways in which population growth can foster development. There are also several rational reasons why families in developing countries may decide to bear many children. Theories on population and development are discussed. Using sub-Saharan Africa as its reference region, the paper describes how rapid population growth can impede development. Current demographic and economic trends in sub-Saharan Africa and the consequences of rapid population growth in terms of economic, environmental, and sociopolitical change, capital widening, the labor force, and trade are presented.