Studying abroad may allow students to form human capital in ways not possible at home and may enable them to earn higher incomes. On the other hand, study abroad has been criticized as insufficiently rigorous. Little is known about how study abroad affects skills and earnings in the long term. Using a data set of 3,155 students over a range of 43 years from a single college, we investigated the effects of study abroad and found it has no net effect on earnings compared with study at home. The advantages and disadvantages of study abroad are approximately balanced; human capital formed by study abroad is not more or less than that formed in residence. Colleges need not emphasize study abroad more than study on campus, but they also need not worry that study abroad is unproductive. Study abroad and study at home appear equally effective at forming human capital.