The wide cross-country disparity in rates of economic growth is the most puzzling feature of the development process. This paper describes a class of models in which this heterogeneity in growth experiences can be the result of cross-country differences in government policy. These differences can also create incentives for labor migration from slow-growing to fast-growing countries. In the models considered, growth is endogenous, despite the absence of increasing returns, because there is a "core" of capital goods that can be produced without the direct or indirect contribution of factors that cannot be accumulated, such as land. Copyright 1991 by University of Chicago Press. (This abstract was borrowed from another version of this item.)