Textbooks and articles on farm management stress the importance of the management capacity of the fanner with respect to his farm results. However, explicit definitions together with an elaboration of this concept are hard to find. In this article, aspects of management capacity are grouped into: (1) personal aspects, consisting of fanner's drives and motivations, fanner's abilities and capabilities and his biographical facts such as age and education; and (2) aspects of the decision-making process, consisting of practices and procedures with respect to planning, implementation and control of decisions at the farm. Empirical studies on the role of management capacity in relation to farm results are reviewed. Frontier production functions are widely used in recent literature to estimate technical and economic efficiency of farms. However, in explaining differences in efficiency most studies do not go further than adding a biographical variable (e.g., level of education). This study concludes that a next step would be to include aspects of the decision-making process. Longitudinal on-farm observations, which give possibilities for studying the dynamic aspects of the decision-making, are suggested to further analyze the concept of management capacity. © 1998 Elsevier Science B.V. All rights reserved.