Prologue: The escalating costs of prescription drugs and competition among pharmaceutical firms for customers are drawing the attention of policymakers, pharmacies, and individual and institutional purchasers. Mail order pharmacies recently have grown in prominence as a competitive alternative to the local community pharmacy. This article by Constance Horgan, Brigid Goody, David Knapp, and Leslye Fitterman explores the one-hundred-year history of mail service pharmacies and the role they play in providing prescription drugs to the elderly. The authors conducted a study of mail service pharmacies, which was mandated by Congress under the Medicare Catastrophic Coverage Act of 1988. Their survey reveals that the elderly account for nearly 57 percent of total sales of mail service pharmacies. At Brandeis University, Horgan is an associate research professor at the Bigel Institute for Health Policy, Heller Graduate School. She holds a doctorate in health policy and management from The Johns Hopkins University ...