This paper touches upon some issues involving decentralisation, efficiency and the role of prices. Some of the ideas brought together here may be of interest to policy-makers interested in the role of the state in the era of 'liberalisation'. The first part of the paper deals with the Walras-Samuelson-Lange process for attaining a Pareto optimal allocation in a socialist economy. In the second part is sketched a Malinvaud-Samuelson type model of an economy evolving over a sequence of momentary equilibria and report on some results on the link between equilibrium and Pareto optimality in the long run.
