The Kaiser Family Foundation – through its Changing Health Care Marketplace Project – sponsors research and analysis on trends in the marketplace, particularly as they affect vulnerable groups like the poor and the elderly, and on policy proposals that involve the private health care system. There have been striking changes in the health care marketplace in the last few years. Some of these changes build on historic trends; others depart, sometimes dramatically, from prior expectations about how the marketplace would evolve. Trends and Indicators in the Changing Health Care Marketplace, 2004 Update (March 2004) presents information on key trends in the health care marketplace of interest to policymakers, public interest groups, the media, and industry analysts and leaders. This chartbook updates many of the exhibits included in earlier reports, Trends and Indicators in the Changing Health Care Marketplace, 2002 (May 2002) and Trends and Indicators in the Changing Health Care Marketplace (August 1998).