Subsequently to the Brundtland Report, the 1992 Earth Summit, and the resu1ting Agenda 21, the issue of population and development has increasingly evolved into discussion on the "population, environment and development nexus". In the face of this new mandate for research on population, environment and development dynamics, theoretical frameworks are limited. Conceptual thinking on population and environment within both the social and natural sciences has traditionally suffered from a long-term confinement within opposing "Malthusian" versus "Cornucopian" views. The work of Ester Boserup, however, continues to transcend the boundaries of this polarized discourse. This paper reviews the main points of Boserupian theory and its relevance to developing regions, in particular to sub-Saharan Africa. Recent reinterpretations of Boserup's work relevant to population and environment relationships in developing countries are also considered.