Critical care medicine is concerned with the provision of organ support systems or life support in critically ill patients who require very, very close monitoring. While these patients may be very ill, their condition is reversible and given good critical care support, they have chances for survival. The possibility for survival is one of the prime requisites for admission to a hospital's critical care unit. Despite the importance of critical care medicine, it is a relatively new specialty. More recently, however, more and more physicians are undergoing training in critical care medicine. These doctors are called intensivists, and there is not enough of them to go around. As a matter of fact, many hospitals lack intensivists. The articles in this section are all about critical care.