The Stock Exchange of Mauritius (SEM) (French: Bourse de Maurice); is an organization responsible for the operation of Mauritius's primary stock exchange located at Port Louis. The SEM operates two markets: the Official Market and the Development & Enterprise Market (DEM). There are 40 companies listed on the Official Market representing a Market Capitalization of nearly US$5.3 billion, the DEM presently has 48 companies listed with a market capitalisation of nearly US$1.5 billion as at 31 July 2012. SEM is one of the leading Exchanges in Africa and a member of the World Federation of Exchanges.