Tata Consultancy Services, Wipro Technologies, and Infosys Technologies are among the top 15 outsourcing vendors in the world.

A recently released META Group's study -- METAspectrum for Leading Outsourcing Vendors (North America) -- says that TCS, Wipro and Infosys are the only Indian firms in the elite group.

META Group is a leading research and consulting firm that focusses on information technology and business transformation strategies.

Also Read India and Outsourcing: Complete Coverage

These Indian IT vendors serve thousands of customers across the United States and Europe (including many Fortune 500 companies), offering software application development and maintenance, IT consulting, business process outsourcing, product design, system integration and remote infrastructure management services.

The study says that outsourcing within North America is growing at an average of 10-15 per cent annually. In contrast, offshore outsourcing is growing at a rate of more than 25 per cent, while mainframe outsourcing is growing at less than 10 per cent.

The other companies in the top 15 are Accenture, Affiliated Computer Services, CGI, CSC, EDS, Hewlett-Packard, IBM Global Services, Keane, Perot Systems, SAIC, Siemens Business Services and Unisys.