Greater Miami Chamber of Commerce. If you have questions or are looking for networking opportunities, contact the Greater Miami Chamber of Commerce at 305-350-7700. The Greater Miami Chamber of Commerce is an association of businesses and professions organized to create economic progress in Miami-Dade County. Its mission is to make South Florida the most business-friendly region in the Americas and to promote members' competitiveness through state of the art benefits and services, support for sustainable economic development, and advocacy to enhance the business environment.