This paper presents some preliminary findings from a research study by the OECD Development Centre into the treatment of subsistence activities in national accounts. It summarizes the results of a questionnaire on country practices, and reports on the findings with respect to shares of non-monetary production in GDP, methods of estimation, and usefulness of the resulting estimates. Among the 48 developing countries covered, the share of non-monetary value added in total GDP ranges from over 40 percent for the poorer countries of Africa to 5 percent or less for the more advanced countries of Latin America and Southern Europe. In countries where rural living standards are much below those in urban areas, non-monetary activities may be very important to the well-being of a large number of people, even though they form only a small part of GDP, and it is still important to make realistic estimates for subsistence output. Agriculture is obviously the main item in non-monetary production, accounting often for over 80 percent of the total. Most countries use some kind of “producers' prices” for valuing agricultural output. Few countries now publish separate figures for non—monetary activities. For many countries, doing so would involve a considerable amount of extra work, but for a number of planning purposes it does seem important to distinguish subsistence activities separately.