The Treasury Market Practices Group (TMPG) was formed in February 2007 in response to the appearance of some questionable trading practices in the secondary market for U.S. Treasury securities. (A history of the origins of the TMPG is available here.) Left unaddressed, the practices threatened to harm the efficiency and integrity of an essential global benchmark market. The Group responded by identifying and publicizing “best practices” in trading Treasury securities—a statement of behavioral norms intended to maintain a level and competitive playing field for all market participants. The Group’s focus expanded in 2008 to include market architecture issues, and again in 2010 to include the federal agency debt and mortgage-backed securities (MBS) markets.