The Society of Industrial and Office Realtors (SIOR) is an international professional commercial and industrial real estate association based in Washington, D.C. It offers a professional designation (SIOR) to commercial brokers and other industry professionals. Its membership is composed of around 3,000 individuals and organizations in more than 630 cities in 32 countries. SIOR designees can hold the following specialty designations: industrial, office, sales manager, executive manager, or advisory service. SIOR also includes associate members, who are corporate executives, developers, educators, and other involved in the commercial real estate industry.