Catastrophic health insurance may be necessary to curb rising health care costs in the United States. A major factor in this rise has been the current structure of the nation's health insurance system, which inadequately protects individuals with expensive illnesses, but encourages over-insurance for less expensive illnesses. This Note examines the current health insurance system, and analyzes its impact on health care costs for individuals and society. It evaluates several proposals to modify the structure of the current health insurance system, and recommends the adoption of a catastrophic health insurance plan based on an economic definition of catastrophe. Such a plan would decrease shallow coverage, and would use coinsurance and deductible rates keyed to the individual's income as means of increasing consumer cost consciousness without making necessary care unreasonably expensive. This Note also recommends that a catastrophic plan only cover treatment that has been determined medically necessary by utilization review, and that this review encourage outpatient rather than costly inpatient treatment.