Standard&Poor's Ratings Services' ratings on Fannie Mae's senior and subordinated debt reflect the U.S. government's ongoing financial support and the Federal Housing Finance Agency's (FHFA) oversight and operating involvement as the regulator and the conservator. The extraordinary support we factor into our ratings on Fannie Mae stems from the firm's status as a public-policy financial institution under our criteria for government-related entities (GREs), as well as its key role in implementing government programs that prevent foreclosures and stabilize the housing sector. Our stand-alone credit profile of 'r' reflects that Fannie Mae is under regulatory supervision owing to its financial condition. Fannie Mae, Freddie Mac, and Ginnie Mae have emerged as the dominant sources of mortgage finance in the