The existence of the present volume can be traced to methodological concerns about cohort analysis, all of which were evident throughout most of the social sciences by the late 1970s. For some social scientists, they became part of a broader discussion concerning the need for new analytical techniques for research based on longitudinal data. In 1976, the Social Science Research Council (SSRC), with funds from the National Institute of Education, established a Committee on the Methodology of Longitudinal Research. (The scholars who comprised this committee are listed at the front of this...