Eaton Vance Corp. is an American investment management firm based in Boston, Massachusetts. It is one of the oldest investment companies in the United States, with a history dating back to 1924. Through five primary investment affiliates, Eaton Vance provides investment products to individuals, institutions and financial professionals in the US, including wealth management, defined contribution investment only and sub-advisory services. In 2005 it opened an office in London. In March 2021, Morgan Stanley completed its acquisition of Eaton Vance, a deal announced in October 2020. With the addition of Eaton Vance, Morgan Stanley now had $5.4 trillion of client assets across its Wealth Management and Investment Management segments.