This is a collaborative research project with Kenneth Wolpin at the University of Minnesota. The purpose of this research is to study the initial phases of career development using data from the National Longitudinal Surveys of Labor Market Experience of Youth. There are three components to the project: (1) to describe the patterns of job and occupational mobility within the first decade after leaving school; (2) to estimate a structural dynamic model of job changing behavior; and (3) to estimate an equilibrium model of occupational choice. This project is important because it may change the way in which we think about the standard human capital model of earnings growth, which neglects job search behavior and labor mobility.