The U.S. equity market is the world’s most liquid, efficient and low-cost. The quality of the markets has, by most measures, improved substantially since 2005, when Regulation NMS was adopted and implemented.
CFA Institute discusses the significant benefits of Regulation NMS and its flaws in response to a Congressional review of the market structure rule. CFA Institute recommends keeping the rule largely as it is, but the vigorous enforcement of broker-dealers' best execution requirements, improved execution-quality data, and updated and enforced price ticks.