This is volume 10 issue 4 of American Journal of Health Economics. The American Journal of Health Economics (AJHE) provides a forum for the in-depth analysis of health care markets and individual health behaviors. The articles appearing in AJHE are authored by scholars from universities, private research organizations, government, and industry. Subjects of interest include competition among private insurers, hospitals, and physicians; impacts of public insurance programs; pharmaceutical innovation and regulation; medical device supply; the rise of obesity and its consequences; the influence and growth of aging populations; and much more. The journal is published for the American Society of Health Economists (ASHEcon), which is a professional, non-profit organization dedicated to promoting excellence in health economics research in the United States.