Case study update. Arizona's UMC model of patient-center care thrives after four years. Three new features of redesign at University Medical Center, Tucson.

In January 1992, this publication introduced a promising one-year-old program of patient-centered care at 312-bed University Medical Center (UMC), Arizona Health Sciences Center, in Tucson. Since then, the groundbreaking program (dubbed the "Arizona Model" by admiring colleagues in other states) has continued to grow, even as the small teaching institution saw its environment evolve into "a war zone" of managed care competition. In the last year, three important enhancements have been implemented.