This paper examines the relationship between the incentives to work and to invest in human capital through education in a lifecycle optimizing model. These incentives are shown to be mutually reinforcing in a simple stylized model. This theoretical prediction is investigated empirically using three large micro datasets covering a broad range of countries. As one might expect, education and work are strongly positively correlated. This correlation has important implications for models of fiscal policy and economic growth. It also has important implications for the estimation of labor supply and the rate of return to education. (Contains 29 notes, 6 figures, and 10 tables.)