The Federal National Mortgage Association (FNMA), or "Fannie Mae" is a government-sponsored enterprise (GSE) whose purpose is to facilitate capital allocation in the residential real estate market. Fannie Mae operates in the secondary mortgage market, expanding the real estate financing market by securitizing residential mortgages into mortgage-backed securities. The firm raises capital by issuing bonds.
Fannie Mae was established as a federal agency in 1938, and was chartered by Congress in 1968 as a private shareholder-owned company. On September 6, 2008, the company was placed in conservatorship by the Federal Housing Finance Agency (FHFA).  Under conservatorship, stockholders in the company were ruined (the stock dividend suspended, the stock delisted, and falling to less than a dollar), while the value of Fannie Mae bonds and mortgage-backed securities were backed by the government.
For investors, Fannie Mae securities come in three forms:
- Stock: Since 1968, Fannie Mae has been a public stock, listed on the NYSE until effective bankruptcy in 2008 forced the government to place the company into conservatorship. The company is delisted, and currently trades in the over the counter market as a penny stock.
- Bond: Fannie Mae bonds are considered government agency (GSE) debentures. Fannie Mae issues benchmark bills®, benchmark notes®, callable medium-term notes, discount notes, subordinated debt, and other debt products.  In 2010, Fannie Mae bond securities comprised 33.2% of the Barclays Capital US Agency Index. 
- Mortgage-backed securities (MBS): Fannie Mae issues pools of mortgages, packaged into Fannie Mae MBS, which Fannie Mae guarantees as to timely payment of principal and interest. Fannie Mae MBS have comprised 47% to 51% of the Barclay's Capital MBS Index over the 2005 - 2010 period.