The housing finance system in the world also studies various types of systems prevailing in housing finance markets. It also studies various traditional and non-traditional means of housing finances, like deposit taking, mortgaged baked security flotation, secondary mortgage market, etc. The process is the collateralization of housing securities for raising funds to meet the long-term requirements of the business.  The roles of government-sponsored enterprises (“GSEs”) have also been delineated. The portfolio acquisition activities of the GSEs expanded in the 1990s. Both Fannie Mae and Freddie Mac increasingly hold mortgage assets on their balance sheet and fund themselves with the issuance of straight and callable debt.