We look at disaggregated imports of various types of equipment to make inferences on cross-country differences in the composition of equipment investment. We make three contributions. First, we document large differences in investment composition. Second, we explain these differences as being based on each equipment type's intrinsic efficiency, as well as on its degree of complementarity with other factors whose abundance differ across countries. Third, we examine the implications of investment composition for development accounting, i.e., for explaining the cross-country variation in income per capita.