By demonstrating the superiority of the present-value to the recoupment-period criterion, Peter Lindert [2] has made a major contribution to the analysis of foreign investment controls. In fact, after reading Lindert's analysis, one wonders how the recoupment-period criterion got a foothold in the first place: the assessment of the net impact of a control program is clearly dependent on a comparison of capital inflows and outflows occurring at different points in time; and the accepted and traditional way to make such intertemporal comparisons is by a present value calculation. While heartily endorsing this methodological shift, one need not be satisfied with Lindert's use of his newly forged tool. In particular, it is my opinion that his policy conclusion is not proved. For two reasons I should like to take issue with his contention that it is impossible for controls on direct investment to help the U.S. balance of payments.' First, his empirical case, while plausible, is open to objection because it rests on that set of assumptions which is most favorable to his conclusion; alternative assumptions lead to the opposite result. This is the subject of section I. Second, Lindert's theoretical condition for the efficacy of a control program does not cover all cases: in particular, for cases, where the limiting rate of growth of foreign investment is higher than the social rate of discount, a different condition holds. In section II, I provide a simple, but general analysis of the problem, one that covers all cases and does not rely on special simplifying assumptions about the shape of the foreign investment path. Empirical evidence presented in this section suggests that the flow of direct investment to important areas of the world falls into the high growth category. Using the proper theoretical condition for this case, the implication is that for a second reason Lindert's policy conclusion may be invalidated.2