Evidence from the 1990 Thai census reveals that the large majority of elderly parents co-reside with at least one child and that this has remained unchanged during the decade of the 1980s despite the rapid and pervasive social and economic development tha t took place. Normative obligations for children to care for and support their elderly parents, including an obligation for at least one child to remain with them, are deeply ingrained in Thai culture and probably account for the persistence of co-reside nce. These findings call into question global assumptions about economic and social change undermining the well-being of the elderly in third world countries.