Water services provision and resource management are devolved functions as per Schedule 4 of the current Constitution of Kenya. A critical determinant of the devolution success in Kenya's WASH sector will be how the County Governments as primary duty bearers will develop resilient WASH supply and management systems that are demand responsive and overall accountable to public needs. Therefore, tackling sustainability issues in WASH services requires a holistic approach focusing on governance and particularly principles of governance: transparency, participation and accountability as to improve service delivery. The USAID-KIWASH Project partners with water service providers in 9 counties including Kakamega County Water and Sanitation Company (KACWASCO) to support them improve and sustain water and sanitation coverage, water catchment protection and credit worthiness. This paper presents an evidence-base case study of KIWASH engagement with KACWASCO that enhanced accountability of its operations, water coverage, revenue collection, resource allocation, customer satisfaction, participation and transparency.