This article discusses the idea of policy coherence for development, and its relation to the experience of development along the Grij alva River in the state of Chiapas, Mexico. Through an analysis of diff erent understandings of the garbage in the river, and of the attempts to deal with the garbage, I highlight tensions between diff erent generations of policies, between diff erent levels of government, and between implementing the goals of governmental representatives and a meaningful participation by citizens. To understand these tensions, the article draws attention to the coexistence of experience-based rationalities, which are important to take into account when formulating policies, and when moving from policies to concrete projects. [ABSTRACT FROM AUTHOR]