The article examines the weaknesses and inefficiencies of the Soviet centralised planning system, and the means by which Gorbachev and his colleagues sought to reform it. Along with the objective difficulties in the way of ‘marketisation’ (lack of practical experience and market infrastructure, lack of agreement about the final objective of reform, obstruction by vested interests, ideological pre-conceptions, popular distrust), grave policy errors were committed (unbalanced budget, inflation ary money-creation, loss of control over incomes, reluctance to increase prices). Meanwhile the rise of natioralism, and the de-legitimation of the regime and of the Party, created a power-vacuum, which by 1991 made impossible the implementation of any policy. Disruption of inter-republican and inter-regional supply links, and drastic cuts in imports, are causing serious declines in production. The failed coup accelerated the process of disintegration.