Large shocks to local labor markets can cause long-lasting changes to employment, unemployment and the local labor force. This study examines the relationship between mass layoffs and the long-run size of the local labor force. It considers four main channels through which the local labor force may adjust: in-migration, out-migration, retirement, and disability insurance enrollment. We show that these channels account for over half of the labor force reductions following a mass layoff event. By measuring the residual difference between these channels and net labor force change, we also show that labor force non-participation accounted for much of the local labor force response in the period during and after the Great Recession.