There is a continuously growing literature on the agricultural transformation in Central and Eastern European countries (see some surveys in Brooks and Nash 2002; Rozelle and Swinnen 2004). The research has focused on various aspects of transition, including land reform, farm restructuring, price and trade liberalisation, but even though Farm Accountancy Data Network (FADN) data are now available for some years, there are only a few studies (e.g. Bakucs et al. 2010, Fogarasi and Latruffe, 2007, Baráth et al., 2009) focusing on Hungarian farm performance. The objective of this paper is to shed light on some methodological issues that are needed to study Hungarian farm performance. Here we consider one aspect of farm performance, namely technical efficiency. This measure refers to whether farmers are capable of using existing technology to its full potential by producing the most possible from a given set of production factor quantities.