The Water Financing Partnership Facility (WFPF) was established in 2006 to access additional financial and knowledge resources from development partners to support the implementation of the Asian Development Bank’s (ADB) Water Financing Program 2006-2020, which committed ADB to an annual water investments of over $2.0 billion or a total of $30 billion by 2020. The WFPF has operated in the overall strategic context of ADB Strategy 2020, and the strategic priorities set out in the 2014 Medium-term Review of Strategy 2020. The evaluation assesses how the WFPF has performed under Phase 1 of its implementation (2006 to 2020). Building on findings and recommendations from the 2010 and 2015 evaluations, the scope of the present evaluation starts in 2015 and seeks to identify how lessons learned could inform the design of WFPF 2021-2030. The evaluation is formative and summative and assesses the relevance, effectiveness, efficiency, and sustainability of the WFPF. Data collection methods have included portfolio review, project deep-dives, semi structured interviews and a benchmarking analysis.