This article draws together results from farm efficiency studies in six Central and East European countries that are part of the EU enlargement process. The main questions addressed concern whether there is a clear superiority of one organisational type, namely, family farms, over corporate structures (production co-operatives and various types of farming companies) and the nature of the relationship between size and farm efficiency. Results from empirical research show that there is no clear cut evidence of corporate farms being inherently less efficient for all farming activities than family farms. Where significant differences have been found in favour of family farms against the average corporate farm, the best corporate farms still tend to perform as well as the best family farms. As far as size in concerned, in countries in transition where small family farms are well established and managed continuously by the present farm household, they appear to be less inefficient compared to larger cohorts as against countries where small family farms are a relatively new phenomenon. © 2003 Elsevier B.V. All rights reserved.