Microeconomically, the case for liberalization is dubious under increasing returns to scale and when firms can invest directly in productiviTY enhancement. Distributional effects of commercial policy changes can be regressive and large, but the 'rents' they generate can serve as a basis for effective policy intervention contingent on firms' performance. Macroeconomically, the case of liberalization rests on Say's Law, which is not always enforced. Recent combined current and capital market liberalizations have been associated with strong exchange rates and high interest rates and output and productiviTY growth have positive mutual feedbacks which liberalization may well suppress.