FOREWORD The Food and Agriculture Organization of the United Nations (FAO) is required by its charter to use the three official languages English, French and Spanish for publication of its documents and, at world conferences, to provide simultaneous interpretation from any one of the three languages into the other two. It is therefore mandatory that equivalents exist for the myriad of terms and concepts used in all of the agricultural sciences. These exist for most of the physical sciences; social sciences have also developed equivalents, but there is still a relatively large number of terms in the science of Farm Management Economics for which there are no universally agreed definitions. In addition, some basic concepts and terms have different meanings or interpretations between agricultural economists themselves. This fact makes it difficult to communicate accurately with the multitude of institutions around the world. These considerations prompted FAO to compare the terminology employed in English, French and Spanish and to establish equivalences between terms. A preliminary version of the glossary was printed and circulated in 1982 in universities and international institutions, with a request for comments and suggestions. Many specialists responded to this demand and their comments have been incorporated to this version. However, this is still considered a draft glossary and the final version is scheduled for 1984/85. Hence comments and suggestions will be appreciated. They should be forwarded to Dr. N.R. Carpenter Chief, Farm Management and Production Economics Service Food and Agriculture Organization of the U.N. Via delle Terme di Caracalla 00100 Rome, Italy