Blue Cross and Blue Shield of Illinois, formerly known as Hospital Service Corporation, is a nonprofit agency that offers a range of prepaid hospital plans. It is one of the largest health insurance companies that provides healthy care plans to more than 6 million members in Illinois. The agency offers a range of managed care programs for individuals, families, employer groups and seniors. It administers the CareVan Program, which provides immunizations and health screenings to underserved communities. Blue Cross and Blue Shield of Illinois features BlueChoice, BlueChoice Select and dental health care plans. It employs a work force of more than 8,000 people. The agency is an independent licensee of the Blue Cross and Blue Shield Association. It is a division of Health Care Service Corporation, which is a customer-owned health benefits company that focuses on improving the health and wellness of its members and communities.