Civil conflicts have afflicted a third of all nations and two thirds of Africa since 1991. In many cases, up to a third of male youth (including children) are drawn into armed groups, making soldiering one of the world’s most common occupations for the young. Little is known, however, about the impacts of military service on human capital and labor market outcomes due to an absence of data as well as sample selection: recruits are usually self-selected and screened, and may also selectively survive. We assess the impacts of participation in civil war using an original survey from Uganda, where a rebel group’s recruitment method provides arguably exogenous variation in conscription. Contrary to the prevailing view that participation in war leads to broad-based ‘traumatization’, we find that military service primarily hinders long-term economic performance because it is a poor substitute for civilian education and work experience. The most significant impact is upon a recruit’s skills and productivity: schooling falls by nearly a year, skilled employment halves, and earnings drop by a third. These impacts are highly robust to relaxation of the assumption of exogenous conscription. Effects are greatest for child soldiers, who lose the most education. There is no observed impact on social capital, and adverse impacts on mental health, while evident, are present in a relative minority.