Lewis Ranieri

Former bond trader and former vice chairman of Salomon Brothers who is credited with introducing securitization to the financial world. Initially, mortgage-backed securities (MBS) were only acknowledged by a handful of states as legitimate investments, but Ranieri's actions eventually led to federal government measures that supported these securities as a valid investment asset class, leading to the development of the bond market.

In 1977, savings and loans banks were feeling the financial difficulties involved with funding short-term, higher interest demand deposits with longer term, low-interest mortgages. As a result, banks did not want to hold onto too many mortgages. By creating five- and 10-year bonds from 30 year mortgages, Ranieri attracted a larger crowd of investors to mortgage-backed securities, which ultimately caused all sorts of debts (such as credit card debt) to be rolled into bonds.