In this book the reader will find a comprehensive consistent discussion of the use of simulation methods in agriculture together with actual models representing the various fields of application. Its aim is to aid micro and macro decision-making and thereby improve the practice of agricultural management by the use of systems simulation and the application of computers. The basic principles of modelling agricultural systems and the general methodology of simulation are described in the opening chapters, followed by chapters on the simulation of production systems in agriculture, the modelling of agricultural enterprises and the modelling of national and international agricultural systems. The Hungarian Agricultural Model (HAM) and the CMEA Agricultural Model and the results attained through their use are also discussed. Finally, the author summarizes the methodological experiences gained by using simulation in agriculture. The book will be useful not only as a manual for managers, agricultural engineers and economists, but also as an aid in various areas of agricultural education and management training.