Goldman Sachs was founded by Marcus Goldman in 1869 in New York. In 1882, his son-in-law, Samuel Sachs, joined the firm; his son Henry and his son-in-law Ludwig Dreyfuss joined in 1885. Today, Goldman Sachs is a banking and securities firm that provides securities and investment management, investment banking and other financial services to its institutional clients. Among other things, Goldman Sachs gives customers advice on mergers and acquisitions, provides underwriting services and prime brokerage, in addition to asset management. There are three main business units within Goldman Sachs, including Trading and Principal Investments, Investment Banking and Asset Management and Securities Services.