Violence against women and girls (VAWG) is an important human rights concern and a pervasive issue affecting women and girls during times of conflict and humanitarian crisis. Over the last five years, the What Works to Prevent Violence Against Women and Girls research programme, funded by UK Aid, has been conducting research to expand the international community’s knowledge around VAWG and the effectiveness of programmes that seek to prevent and respond to this violence. This new brief synthesises the key results of What Works studies as well as other findings from contemporaneous research efforts published since 2015. It aims to provide an up-to-date resource for practitioners, policymakers and researchers on the state of evidence on VAWG in conflict and humanitarian settings and makes recommendations for VAWG policy, programming, and future research priorities.