Evidence is central to effective and rigorous development programming. The generation of evidence was a priority under Phase I (2016-2019) of the Global Programme to End Child Marriage (GPECM), which is implemented by the UNFPA Asia Pacific Regional Office (APRO) and the UNICEF Regional Office for South Asia (ROSA). This study was conducted in Bangladesh, India and Nepal at the start of Phase II to establish a baseline measuring the programme’s use of evidence in programming, design and delivery, advocacy and monitoring and evaluation (M&E). The study also reviews the major activities outlined in the Phase II Work Plans for the three countries. The study develops a set of core indicators and tools for measuring the use of evidence that can be replicated at the mid-term and at the end of Phase II.