The world's largest and most profitable companies?including the likes of GE, Bank of America, Honeywell, DuPont, Samsung, Starwood Hotels, Bechtel, and Motorola?have used Six Sigma to achieve breathtaking improvements in business performance, in everything from products to processes to complex systems and even in work environments. Over the past decade, over $100 billion in bottom-line performance has been achieved through corporate Six Sigma programs. Yet, despite its astounding effectiveness, few outside of the community of Six Sigma practitioners know what Six Sigma is all about.