There is considerable interest in moving beyond static investigations of job performance to studying the dynamics of job performance over relatively long periods of time. In the present research, we investigated the development of job performance using a large sample of 420 employees followed over a six-year period for which yearly job performance evaluations by managers were available. Latent growth models indicated the presence of a nonlinear trajectory, with alternating phases of stability, sharp increase, and abrupt decrease. Level of education, the perception of one’s direct supervisor, and self-efficacy significantly predicted individual job performance levels observed at Wave 2. Quadratic job tenure, level of education, the perception of one’s direct supervisor, and self-efficacy were found to be significant predictors of job performance development. Findings are discussed in the light of their implications for future studies examining job performance longitudinally.