We use data from the NFL over 1920–2004 to examine the relationship between age and managerial performance controlling for other relevant influences. Our results indicate that age enhances performance up to a point at which increasing age predicts diminished performance—a managerial life cycle. Moreover, rates of change in the life cycle are relatively gradual, which is consistent with gradual changes in the marginal product of human capital and depreciation rates for human capital rather than levels that are fixed for long periods. With a lag of about 7–10 years, the effects are very similar to those found between age and athletic performance in previous studies by Fair. Copyright © 2006 John Wiley & Sons, Ltd.