The founders of a respected Silicon Valley advisory firm study legendary category-creating companies and reveal a groundbreaking discipline called category design. Winning today isn't about beating the competition at the old game. It's about inventing a whole new game-defining a new market category, developing it, and dominating it over time. You can't build a legendary company without building a legendary category. If you think that having the best product is all it takes to win, you're going to lose.