Water is an important natural resource, indispensable for life and also the backbone of growth and prosperity for mankind. Kenya is a water scarce country with renewable fresh water per capita at 647m3 against the United Nations recommended minimum of 1,000m 3 . Despite the efforts made by the Government of Kenya, Unaccounted-for-Water (UFW) is still high, currently standing at 49%. The overall objective for this study was to assess the strategies for reducing UFW in water supply systems. The scope focused in identifying areas for improving the water supply systems at NZOWASSCO. The target population was 148 employees. Data was collected through questionnaires and analyzed using Statistical Package for Social Sciences (SPSS). Descriptive and inferential statistics were used to present the results. The research findings indicate that majority of employees working in water supply systems are in operations level, considering that majority are diploma holders, their capacity should be enhanced. The research confirmed that on average, the level of Unaccounted-for-Water at NZOWASSCO was at 45%, this is in concurrence with the 2010 Impact Report by WASREB. It was further established that implementation of appropriate strategies to reduce UFW enables water supply systems to serve more customers for longer periods and thus WSPs realize high revenue.