This monograph began as a study of the consequences of labor force effects, in- cluding unemployment, for the distribution of earnings. I began by developing a model of job search. But following my previous work on the distribution of earnings, the search theory took a different form from the standard literature. Workers and firms were engaged in mutual search which effectively assigned workers to jobs. A number of open questions immediately became apparent, including the relation bet- ween unemployment and inequality, the nature and costs of unemployment, and the role of choice. These quickly provided sufficient material for the monograph. I began work on the project in 1980 at Miami University of Ohio. I wish to thank my chairman there, William McKinstry, for the support I received during my last year there. My colleagues Donald Cymrot and James Moser provided some early com- ments on the project and I am indebted to Joseph Simpson for extensive computer assistance.