Using 1980 census and 1987 survey data on birth cohorts to examine recent primary and secondary school enrollment trends [in Thailand], this study reports that primary enrollment is nearly universal but secondary enrollment is much less prevalent. The study assesses several factors thought to influence enrollment and finds that urban residence, parents' completion of primary school, the mother's positive attitude toward education, and the family's being comfortable economically to be associated with children's enrollment in secondary school. It also indicates that, for moderately well-off families, proximity to schools has a major influence on secondary school attendance. For the wealthiest families, however, distance is not a hindrance to attendance, and for the poorest families, having a school nearby is not sufficient to ensure attendance.