This paper explores the implications of the vast body of studies of cross-country growth determinants for the evaluation of alternative policies. Empirical growth studies have experienced a remarkable flowering in the last fifteen years, and innumerable insights have unquestionably been uncovered concerning similarities and differences in the growth experiences of various groups of countries. This empirical work was stimulated by—and, in turn, has been an essential complement to—the revival of growth theory initiated by the seminal papers of Lucas (1988) and Romer (1986). It constitutes one of the great successes of recent macroeconomic research.