When they set out to turn around processes that have become woefully inefficient or ineffective, most companies choose one of four process improvement “religions”: Lean, Six Sigma, Business Reengineering or Business Process Management (BPM). After hearing about its success at another organization, many companies choose just one. For example, several companies embarked on Six Sigma programs after their CEO heard about GE’s success with the approach, and many other companies have adopted Lean because of Toyota’s success. It’s like adopting a diet or exercise program that a friend has used and lost 50 pounds.