The Statistical Development Series is a sequence of comprehensive technical manuals on various aspects of the statistical programmes which make up a national information system for food and agriculture. The volumes Food and Agricultural Statistics in the context of a Rational Information System. Programme for the 1990 World Census of Agriculture and its Supplement for Europe, and microcumputer based Data Processing have already been published, An additional volume, Guidelines on Socio-Economic Indicators for Monitoring and Evaluating Agrarian Reform and Rural Development is in preparation. In the Statistical Development Series emphasis is placed on the need to conceptualize data source within the framework of a national information system which requires standardized concepts and minimizes duplication of effort.