Types/Cost of Membership Contractor Membership A contractor is defined as a construction firm, which may or may not act as a prime contractor, but does undertake work on projects in part or whole using its own jobsite workforce.  Supplier/Service Provider Membership A Supplier/Service Provider member is defined to be any individual, partnership or corporation who does not contract to perform construction work. Supplier/Service Provider members supply materials, equipment, services to contractors doing building, highway, heavy engineering and municipal/utility construction.