COSIDER was created on 1 January 1979 as a company bursar Mixed by National Steel Company (SNS) and the Danish group Christiani and Nielsen. In 1982, COSIDER becomes a 100% subsidiary of SNS following the purchase by the latter of the actions of Danish partner. As part of the organizational restructuring of public enterprises decided by the Algerian authorities, COSIDER is transformed national company in 1984 under supervision of the Ministry of Heavy Industry. In favor of law enforcement and economic reforms, including those relating to the autonomy of public enterprises in 1988 COSIDER was transformed into a joint stock company in October 1989. COSIDER was able to create and exploit various opportunities that have allowed him to develop and expand its scope of action to other activities not only of the building industry and public works. Unlike its competitors present on the local market, COSIDER, encouraged in this by its stability and entrepreneurial spirit, is committed to diversify, in the space of a decade, its business portfolios and clients. Continuous assessment through internal growth, made COSIDER the largest group of Algerian BTPH Today COSIDER GROUP SPA capital of 4.335 billion DA, is organized into a group of companies which owns 100% of the capital ten (10) subsidiaries. It occupies the first place in Algeria BTPH and fifth in Africa (Africa intelligent young). It is also 48 billion dinars in sales and more than 18,500 employees These performances are the result of a strong sense of organization and discipline, it is also the result of a culture of strong company that has brought together the best talent to build teams of highly motivated employees.