This study was aimed to identify the forests and agro-forestry systems (AFS) that provide important ecosystems services (ES) for vulnerability reduction to climate change in the potable water sector in Nicaragua. Forests areas and AFS important for the potable water sector were deter-mined from data about and uses, their capacity to provide ES, benefits obtained by ES users, location of the users, and vulnerability indices in the context of climatic change. Data were processed by a mathematical model and a geographical information system. Results show that important forests and AFS are mainly located in the Pacific and Central regions and that only 20% of the important to very important forests are protected by the protected areas system. These results provide insights on the adaptive management measures for forests and AFS that would reduce the vulnerability of the potable water sector facing climate change. (Résumé d'auteur)