Regional, private, nonprofit components of managed care systems that purchase health care benefit packages for small employers and individuals. They act as cooperatives between government and the public so that health plans in a region conform to federal benefits and quality standards and keep costs within a mandated budget. They enroll individuals, collect premiums, purchase enrollee’s insurance from participating health plans, and enforce rules that manage health plan competition. Also referred to as alliances, health insurance purchasing cooperatives (HIPCs), health insurance purchasing corporations, health alliances, regional health alliances, health plan purchasing cooperatives (HPPC), or purchasing group.