According to The Handbook of Program Management by James Brown, A Program Manager is the individual who is responsible for delivering a major product or service, while improving that product or service AND enabling the organization to continuously outperform the competition.

A project manager’s role is to ensure that the project stays within the constraints set at a program or upper level.  These usually consist of cost, schedule and scope.

The program manager’s role is more complex.  They may be managing multiple projects simultaneously as well as defining policy, setting objectives, establishing culture, handling operational responsibilities and are accountable for profit or cost margins linked to business strategies.