Despite ubiquitous discussions of robots' potential impact, there is almost no systematic empirical evidence on their economic effects. In this paper we analyze for the first time the economic impact of industrial robots, using new data on a panel of industries in 17 countries from 1993-2007. We find that industrial robots increased both labor productivity and value added. Our panel identification is robust to numerous controls, and we find similar results instrumenting increased robot use with a measure of workers' replaceability by robots, which is based on the tasks prevalent in industries before robots were widely employed. We calculate that the increased use of robots raised countries' average growth rates by about 0.37 percentage points. We also find that robots increased both wages and total factor productivity. While robots had no significant effect on total hours worked, there is some evidence that they reduced the hours of both low-skilled and middle-skilled workers.