The Mourides' global business hub
Tim Judah visits Sandaga market in Dakar, Senegal, which is the business hub of the Mouride Brotherhood - a branch of Sufi Islam dedicated to work and social welfare.
There is an estimated three to five million Mourides living in Senegal, and many more around the world, and followers have developed a global network which facilitiates international trade.
The full report was broadcast on Radio 4's Crossing Continents on Thursday, 4 August 2011. Listen again via the Radio 4 website, or by downloading the podcast.