ABSTRACT
Historically, research on optimal growth-paths preceded the Harrodian concern with the search for conditions of stability of equilibrium growth. The theory of optimal growth has seen interesting extensions, some of them connected with the theory of decentralised planning. Consideration of optimal growth has needed to allow for the problems created by the existence of natural exhaustible resources, allowance for which has been a feature of the recent development of economic research on growth. The limited availability of natural resources does not, however, appear to be the only limit to growth.
