This talk was given at the 4th Annual Catholic Medical Association Medical Student and Resident Boot Camp held at St. Charles Borromeo Seminary in Wynnewood PA on June 23, 2016. In this talk I explain the Principle of Double effect and touch on some of the other fundamental principles in a Catholic approach to health care. I also take two examples which the Magisterium has pronounced on explain them. The examples are Artificial Nutrition and Hydration and Uterine Isolation.