Established over 20 years ago, Maintenance Systems Management Inc. is one of the leading providers of contract custodial, janitorial and maintenance services in the United States. Based in San Francisco, Calif., the firm provides a variety of custodial and janitorial services for single office spaces and multi-tenant office buildings, retail businesses, car dealerships, clothing stores, restaurants and cafes, to name a few. In addition, it also caters to medical and biotechnology offices, laboratories and clean rooms, high-tech hardware and software companies as well as banks and financial institutions, among others.