During the past seven years, extensive research at Bain & Company focused on how companies create and sustain profitable growth. The work has been highly empirical, building on sources like a 20 year data base of 8000 companies' performance patterns, over 150 interviews with senior executives, and hundreds of case studies. Most companies' strategies follow a life cycle of Focus-Expand-Redefine. Many companies today are about to redefine their strategy.