Alten is a holding company. Through its subsidiaries, Co. operates in three areas: Engineering and Technology Consulting (ETC), Telecoms Networks and Multimedia, and Information Systems (NTIS). Through the Engineering and Technology Consulting (ETC) segment, Co. studies and designs technology products for technical divisions in industry and telecoms. The Telecoms Networks and Multimedia segment focuses on Product design, Architecture, deployment, and operation of networks. Lastly, the IT systems segment comprises Applications and software development, and Infrastructure and Telecoms (Applications, systems and networks Corporate telecommunications).

Indra Sistemas is engaged in the design, development, manufacture, assembly, repair, and installation of computer software and applications. Through its subsidiaries, Co. is engaged in consulting, graphic design and multimedia, web design and marketing, internet development and electronic trade, systems integration and hosting geared business to business and business to consumer, as well as in internet financing and electronic marketing. Co. serves defense and security, transport and traffic, energy and industry, telecom and media, finance and insurance, and public administration and healthcare markets. Co. operates primarily in Europe, the United States, Canada, and Latin America.