In the 1980s, many CEOs and senior management teams operated in isolation. A reimbursement system designed to encourage competition led to a "survival-of-the-fittest" mentality that prompted many managers to develop "competitive strategies" and look for "niche opportunities." In many cases, the end result was a fragmented delivery system with--in some instances--gaping holes. Now, CEOs are looking for ways to put the pieces back together. The first part of this cover story examines the issues surrounding the rapidly emerging trend of regional delivery systems; the second part, which begins below, looks at four case histories of different types of integrated systems at various stages in their development.