This book analyses and compares the unofficial economies and their control in ten marxist states: the USSR, Poland, Hungary, Romania, Yugoslavia, Cuba, Nicaragua, China, Angola and Tanzania. It provides a vivid, mosaic-like panorama of the hidden economies in these countries. The book breaks with the view that the unofficial economy is simply a by-product of the official economy. It shows an unfolding interplay between these two economies, which moulds and limits both the dynamics and the direction of the process of change. In her final essay, Maria Los develops a theoretical model linking second economies with the process of marxist economic development. The key stages of this process are identified as: (1) The stage of radical transformation, (2) The monopolisation period, (3) The reformist phase, and (4) Post- reformist decadence. The volume throws a new light on the prospects and problems of the reformist movements which have swept the Soviet Union, China and several other marxist states in the 1980s.