By David Bamford
BBC News Africa analyst
An West African aid group campaigning to abolish female genital mutilation has been awarded the world's biggest prize for humanitarian work.
Female circumcision is widespread in many parts of Africa
The Tostan organisation, based in Senegal, has been chosen for the Hilton Prize, worth $1.5m (£740,000)
The organisation uses traditional song, poetry, theatre and dance to educate people in West African villages about the dangers of genital mutilation.
Prize judges said Tostan had nurtured new ways of dealing with the issue.
Tostan's 400 staff are mostly African workers.
Their grassroots approach has been key to dealing sensitively with an issue that involves convincing traditional communities they should move away from a long-maintained yet cruel cultural practice.
The Nobel prize-winning economist Amartya Sen, one of the Hilton prize jurors, said that Tostan's founder in Senegal, American-born Molly Melching, had nurtured a fresh approach by persuading a critical proportion of the population to agree with you and then act in unison.
The name Tostan is from the local Wolof language, meaning "breakthrough".
The prize is awarded annually by a foundation set up by the hotel entrepreneur Conrad Hilton.