CENTURY 21 Group One is a real estate firm that serves the Blackwell, Braman, Kaw City and Newkirk communities in Oklahoma. The company deals in the buying and selling of residential and commercial properties. It is a part of Century 21 Real Estate, which is the franchisor of one of the world s largest residential real estate sales organizations. The parent company provides training, management, administrative and marketing support services. It comprises more than 8,300 independently owned and operated franchised broker offices in over 50 countries and territories worldwide. Century 21 Real Estate is a subsidiary of Realogy Corporation, which is a global provider of real estate and relocation services. CENTURY 21 Group One has a presence in Ponca City, Okla.