A landmark Foundation-initiated study by the RAND Corporation found that Americans receive only half of recommended medical care.1 This study added to the mounting evidence of quality deficiencies in the U.S. health care system, which was brought to the forefront in a 2001 Institute of Medicine report documenting the chasm between the care Americans have now and the care Americans should have.2 A new study from this RAND research project asks the next logical question: How are patient characteristics such as age, gender, race/ethnicity and income associated with the quality of health care received? This question has been widely studied, but largely as it relates to whether an encounter with a provider occurs. Whether necessary preventive measures, treatments or procedures are provided at similar rates to individuals with different social and demographic characteristics is less understood.