Lead Underwriter Arranger Lead Manager Managing Underwriter Bookrunner A bookrunner, also known as a lead underwriter or lead manager, is a financial institution or investment bank responsible for managing the issuance of new securities, such as bonds or stocks, in a public offering. The bookrunner coordinates the syndicate of underwriters, sets the price of the securities, and allocates them to investors, playing a crucial role in the success of the offering.