Violence against women and girls (VAWG) is the most widespread form of abuse worldwide: globally, one in three women is beaten or sexually abused by an intimate partner in her lifetimei. DFID’s £25 million flagship ‘What Works to Prevent Violence’ research and innovation programme, which launched in 2014, engages leading international experts to produce rigorous evidence on the most effective interventions to drive down rates of VAWG. The evidence being generated is a global public good, intended to help DFID, developing country governments and international partners everywhere to improve the effectiveness of their efforts to prevent VAWG.