Gartner analyst Linda Cohen offered that forecast after arguing that businesses need a new approach to outsourcing, one that's disciplined, not ad hoc -- especially as companies deal with more and more service providers. 'You are heading for a much more complex operating environment where you have more services delivered externally,' she said.

Gartner's global outsourcing forecast reflects that view. It envisions worldwide annual growth for IT and business process outsourcing (BPO) services at 5.5 percent, rising from US$582 billion in 2004 to $760 billion by 2009.

Outsourcing services is still a relatively new practice for many companies, driven in part by interest in leveraging savings from offshore projects. Key to managing multiple vendors, according to IT leaders at Du Pont Co. and ABN AMRO Bank NV, is retaining strategic planning and architecture in-house.

Bruce Jacobs, CIO of the North American operations at ABN AMRO, is outsourcing infrastructure, applications and development and telecommunications services. In fact, the company has five vendors now delivering application services, including Infosys Technologies Ltd., Tata Consultancy Services Ltd., Accenture Ltd., IBM and Patni Computer Systems Ltd.

Under the model ABN AMRO is using, those five vendors compete for contracts and must work as a team on a 'peer-to-peer relationship,' said Jacobs. The bank has, in effect, created an 'internal market' for contracting application development work globally, he said. It finalized the arrangement with the five vendors last September.