400 East 55th Street Assoc is a business entity located at 400 East 55th Street. While specific offerings are not detailed, the name suggests it may be associated with real estate or property management, given the address-based title. Situated in a potentially prime location, this business could be involved in managing residential or commercial properties, providing leasing services, or engaging in real estate development. The exact nature of its services would depend on further context regarding its operations and business focus.