Book excerpt: This report summarizes presentations and discussions at the Workshop on the Social Processes Underlying Fertility Change in Developing Countries, organized by the Committee on Population of the National Research Council (NRC) in Washington, D.C., January 29-30, 1998. Fourteen papers were presented at the workshop; they represented both theoretical and empirical perspectives and shed new light on the role that diffusion processes may play in fertility transition. These papers served as the basis for the discussion that is summarized in this report.