T. Mark Jones learned about the costs and benefits of health-care delivery when he treated AIDS patients in Key West, Florida, in the late 1980s. The pharmacy he co-founded -- unusual at the time -- provided a humane last step for gay men who didn't want to spend their final weeks confined to a hospital. Jones, a registered nurse, went into homes to dispense infusion-therapy drugs and teach patients to care for themselves. His dream job began to unravel in 1991, when a national health-care chain came to Key West to open an AIDS clinic. It secured the support of local doctors by offering them padded insurance reimbursements, Jones says, Bloomberg Markets magazine will report in its September issue.