Summary: Massachusetts has enjoyed one of the most successful economic transitions to a knowledge-based economy anywhere in the world over the last two decades. Statewide trends describe a solid economic turnaround, built on strong institutions, soaring educational attainment and the emergence of knowledge-based industries with high-paying jobs. Yet these broader trends obscure stark geographical variations within the state. On the one hand, Greater Boston has evolved into an even more dominant focal point of the Massachusetts economy than it was 30 years ago. On the other hand, only a few Massachusetts cities and regions are fully participating in the state’s economic reinvention, and the state’s traditional mill communities – the Gateway Cities –may actually be falling farther behind.