Historian Christy Ford Chapin of University of Maryland Baltimore County and Johns Hopkins and author of Ensuring America's Health talks with EconTalk host Russ Roberts about her book--a history of how America's health care system came to be dominated by insurance companies or government agencies paying doctors per procedure. Chapin explains how this system emerged from efforts by the American Medical Association to stop various reform efforts over the decades. Chapin argues that different models might have emerged that would lead to a more effective health care system.