Problems of developing countries that could be addressed with studies of time use are identified and associated methodological issues are discussed. Time use studies investigate how individuals allocate time among various activities. Such studies have revealed sex and age differences in time spent at work among adults and children of various societies, thus providing a view of the extent of women's and children's work and a perspective on the choices women make about their children when time is scarce. However, in order to meet quality standards in the quantitative social sciences, more stringent efforts must be made to improve the quality of time use data being collected. As a step toward this end, ten time use studies from developing countries using three kinds of methodology (observation, sequential recall and activities recall methods) are examined and ranked in terms of 12 methodological issues. Issues raised include problems of reliability, validity, coding, justifications for age classifications of children, sample coverage and quality of time use. Methodological improvements for time use studies are suggested. (Author/RH)