This report captures the results of a joint exercise by UNFPA and Avenir Health to estimate the cost and impact of scaling up programmes addressing female genital mutilation. A combination of programme data, secondary data analysis and population-level costing methods were used to calculate cost and impact in 31 countries with a high burden of the practice. As the first exercise of its kind, the report provides new evidence to inform advocacy and programmatic interventions addressing female genital mutilation at different levels. It also provides a starting point for similar undertakings in the future.