ABSTRACT. In Madagascar, the constellation of taboos serves as a form of informal regulatory institution and is foundational to Malagasy culture, regardless of class, ethnic group affiliation, and educational background. Many researchers have credited rapid social change as a crucial mechanism for disturbing taboos. Others suggest that taboos are innately historical. However, very little empirical research has assessed the effects of social change on taboos or quantified the stability of taboo systems over time. Here, we use a case study of the ensemble of taboos in northeastern Madagascar, still a critical aspect of social life there, as a lens through which we investigate its degree of stability over time. Our aim was: (1) to describe the food taboos of local Malagasy living in northeastern Madagascar, and (2) to quantitatively assess the stability of these taboos to address certain claims regarding cultural erosion using an empirical, hypothesis-driven approach with rich ethnographic material to aid in interpretation. We investigated the temporal stability of taboos and local adherence to the moral framework, finding that approximately 3.0% of 4857 taboos were not adhered to at least once during the course of a 7-yr follow-up study. Additionally, we quantitatively explored the mediating effects of migration, modernization, and the spread of Western religion on number of taboos and level of adherence. We found that the presence of extralocal groups and migration did not decrease the number of taboos abided by locally, but did increase rates of nonadherence. Modernization accompanied by generational shifts tended to increase rather than erode the number of taboos, and younger individuals adhered to taboos to the same degree as older individuals. The effect of Western religion depended on the denomination, but generally reduced the number of taboos, although it did not affect adherence. The ways in which social change affects the stability of taboos are complex. Migrants tended to adhere to taboos less than long-standing inhabitants, suggesting that attachment to place is significant in maintaining adherence to taboos.