As healthcare undergoes a transformation to a value-based, accountable care model, John Porter may be blessed with just the right background to lead a major health system: He has none. Well, that is, he had no clinical or management training in healthcare and never aspired to a healthcare career, but he has spent his last 40 years running Avera, a Sioux Falls, S.D.-based health system with more than 300 locations – including 32 hospitals – in South Dakota, North Dakota, Nebraska, Iowa and Minnesota.