In this paper, we follow on the seminal work of Altonji and Shakotko (1987) and Topel (1991) and reinvestigate the returns to seniority in the U.S. These papers specify a wage function, in which workers’ wages can change through two channels: (a) returns to their seniority; and (b) returns to their labor market experience. We start from the same wage equation as in previous studies, and, following our theoretical model, we explicitly include a participation-employment equation and an interfirm mobility equation. The employment and mobility decisions define the individual’s experience and seniority. Because experience and seniority are fully endogenized, we introduce into the wage equation a summary of the workers’ entire career and past job...