This four-chapter book explains how the structure of job opportunities in the United States has changed over the past 20 years as the economy has changed from goods production to service employment; it links such changes to the issues of displacement policy and worker mobility. It is intended to contribute to the formation of policies and programs designed to help workers adjust to economic change. The first chapter outlines changes in the structure of job opportunities and assesses their effect on the post-layoff adjustment process of displaced workers and policies to facilitate it. Chapter 2 focuses on how the structure of job opportunities in the United States has changed in the recent past, explaining the issues and problems these changes may pose for successful worker adjustment. Analysis was made through data supplied by the March Work Experience Supplements to the Current Population Survey (CPS). Chapter 3 assesses the manner in which displaced workers have responded to changes in the structure of jobs and the implications that emerge for program policy. Data used were obtained from the January 1986 Dislocated Worker Supplement to the CPS. The final chapter draws together the conclusions from the analyses to identify the major challenges faced by programs and policies designed to facilitate worker adjustment to economic change. It discusses realistic policy goals and their implications for program strategy. Forty-two tables, extensive notes, and an index are provided. (KC)