Gateway architecture LLP is a full service architectural and design firm with licenses in 6 states. NCARB certification and leed accreditation headquartered in Alton. IL with an additional office in ST. Louis. MO. Founded in 2012 by TWO experienced architects WHO were interested in bringing personal service along with sustainable design to metropolitan ST. Louis area. The firm philosophy is that of service to the client. Design for the Client’s needs. And exceed Client’s expectations.