This study reassesses a body of research that has been somewhat neglected: Eastern European market socialism of the 1960s-1980s. It does so with the objective of recovering key issues and also identifying problems that need to be addressed. Thus, the study begins with an overview of the practices of market socialism, which was pursued to varying degrees from the 1960s. While some (USSR, East Germany and Czechoslovakia) turned back to centrally planned economies in the 1970s, others (especially Yugoslavia and Hungary) pursued further reforms. This material provides the basis for analysis of three theoretical points and their attendant problems: the market as a neutral 'economic mechanism', as an effort to detach a market economy from its assumed integral connection with a capitalist socio-economic system; the tensions between planning and market; and the ownership of the means of production, which risked ignoring the liberation of productive forces. The conclusion discusses potential assessments of the market socialist experiments.