Technical efficiency of wheat farms in eastern England is measured through the estimation of a stochastic frontier production function using panel data for the 1993-1997 crop years. Variations in the technical efficiency index across production units are explained through a number of managerial and farm characteristic variables following Battese and Coelli (1995) [Empirical Econ. 20, 325-332] and incorporating the spirit ofRougoor eta!. (1998) [Agric. Econ. 18, 261-272]. The technical efficiency index across production units ranges from 62 to 98%. The objectives of maximising annual profits and maintaining the environment are positively correlated with, and have the largest influence on, technical efficiency. Moreover, those farmers who seek information, have more years of managerial experience, and have a large farm are also associated with higher levels of technical efficiency. Future studies that seek to explain variation in technical efficiency should include further aspects of the managerial decision-making process. © 2001 Elsevier Science B.V. All rights reserved.