Like many beliefs about Toyota, however, this doesn’t serve executives well. It’s a half-truth, and half-truths are dangerous. We studied Toyota for six years, during which time we visited facilities in 11 countries, attended numerous company meetings and events, and analyzed internal documents. We also conducted 220 interviews with former and existing Toyota employees, ranging from shop-floor workers to Toyota’s president, Katsuaki Watanabe. Our research shows that TPS is necessary but is by no means sufficient to account for Toyota’s success.