This sector is composed of companies that manufacture healthcare equipment and supplies, and provide healthcare-related services. This sector also includes distributors of products and providers (owners and operators) of healthcare facilities and organizations. Also included in this sector are the companies involved in the research, development, production and marketing of pharmaceuticals and biotechnology products. Providers of diagnostic, preventive, remedial and therapeutic services such as doctors, nurses, hospitals and other private, public and voluntary organizations are listed under this sector as health insurance firms.