An assessment was done of the sustainability of water, sanitation, and hygiene (WASH) interventions completed in the Dominican Republic under the International H20 Collaboration between Rotary International and the United States Agency for International Development. The Dominican Republic is one of three pilot countries where this Alliance was operationalised. This publication presents the results of an assessment of a range of interventions including: newly constructed or rehabilitated community reticulated systems, shared or private household latrines, school or institution sanitation facilities, hygiene/hand washing promotion, and household water treatment. This document presents a detailed overview of the WASH sector and the methodology used in the assessment along with the results of the data collection, analysis and final recommendations.