We analyze the dynamics of worker mobility in the United States over the 1968-1993 period
at various levels of occupational and industry aggregation. We find a substantial overall
increase in occupational and industry mobility over the period and document the levels and
time trends in mobility for various age-education subgroups of the population. To control for
measurement error in occupation and industry coding, we develop a method that utilizes the
newly released, by the Panel Study of Income Dynamics, Retrospective Occupation-Industry
Supplemental Data Files. We emphasize the importance of the findings for understanding a
number of issues in macro and labor economics, including changes in wage inequality,
productivity, life-cycle earnings profiles, job stability and job security.