This report assesses Medicaid MCO quality scores as published annually by NCQA.  One of the report’s key findings is that there does not appear to be any relationship between Medicaid MCOs’ enrollment levels and their quality scores.  Another is that high-scoring plans are disproportionately concentrated in certain states – with these patterns often recurring (with different health plans in these same states) with regard to quality scores in the Medicare and private insurance sectors.  This leads us to conclude that some geographic areas are more conducive to high scores than others – and that MCOs making the same efforts in quality would likely obtain very different quality scores based on the market area in which they operate.  Our report also identifies the Medicaid MCOs with both large enrollment and high quality scores, the MCOs that stand out most favorably relative to average scores within their state, and the NCQA-accredited MCOs achieving the greatest improvements in their quality scores between 2010 and 2013.