GIS modelling and data analysis can increase efficiency in water service management and delivery, data processing, calculations, reporting and decision-making, thus creating a powerful platform for water loss management interventions. NAWASA identified GIS-based monitoring and control approaches as a suitable management tool to reduce water loss across the country. Through CTCN technical assistance, the Climate Technology Network member Wood Public Limited Company and the Caribbean GIS solution provider GISCAD Ltd. supported NAWASA to establish in-house GIS structures and procedures, build capacity for data management and system integration, and apply GIS technology in pilot district metered areas. First, Wood Public Limited Company and GISCAD Ltd. reviewed and refined the available data sets, before training NAWASA staff on the use of new GIS-based data collection tools and on the detailed mapping and remapping of the pipeline distribution network in two pilot zones, which more than doubled the recorded pipe network length. Then, joint work was undertaken to digitize meter readings and locations and workflows for the leak detection crew and for the capture of materials used to improve inventory management. Finally, the new data sets were integrated in a web-based GIS mapping platform to visualize the findings and achievements.