The “Decentralised Supply and Water Use Management in the Sana’a Basin” project was designed to promote sustainable water resources management. The evaluation found the project to be highly relevant to the country’s needs and effective in contributing towards improved livelihoods resilience. The evaluation highlighted project’s contributions towards enabling environment for the provision of public services to farmers, and establishment of water user associations that were integral to the decentralisation of groundwater usage regulation. The project helped farmers to identify more sustainable alternatives to their cropping systems and groundwater usage. For results sustainability, local context and climate-related data should be better analyzed prior to demonstration of new methods and approaches for adaptation activities. In addition, groundwater abstraction projects should be designed with longer duration and with more effective and regular monitoring of progress to inform timely adjustments.