As the income gap between developed and developing nations grows, so grows the cacophony of voices claiming that the quest to find a simple recipe for economic growth has failed. In sharp contrast, this work reports the good news about global progress. The author, an economist, argues against development naysayers by pointing to the evidence of widespread improvements in health, education, peace, liberty, and even happiness. He shows how the spread of cheap technologies, such as vaccines and bed nets, and ideas, such as political rights, has transformed the world. He also shows that by understanding this transformation, we can make the world an even better place to live. That's not to say that life is grand for everyone, or that we don't have a long way to go. But improvements have spread far, and, according to the author, they can spread even further.