This article presents part of the results of a doctoral dissertation concerned on sustainable sanitation in Costa Rica. Specifically, this article relates to environmental sanitation policies implemented in the country. Environmental sanitation is a complex concept because it implies the integration of different aspects related to drinking water, sanitation, and the management of solid waste; and its diverse implications in terms of improving human well-being and environmental conditions, especially in contexts of poverty and social exclusion. Thus, efforts must be directed to the legal obligation of governments to commit themselves to attain sustainable development goals under the notion of people’s basic right to live in a healthy environment. Social work advocacy plays a major role in promoting policy changes by positioning the issue at the top of national and local agendas as well as looking for improvements in terms of planning and implementation of projects.