Both critical illness and treatment in the critical care unit are extremely stressful, presenting great physical and psychological challenges for patients and their families. There are a range of compensatory responses to stress which may be adaptive, but severe or prolonged stress can induce a destructive spiral of decompensation. The importance of a holistic approach to care cannot be overemphasized; this chapter sets out the priorities of care for critically ill patients, and the common needs and problems for both patients and their families. The issues discussed include the mechanisms of stress in critical illness, the promotion of sleep, use of analgesia and sedation, management of delirium, complications of immobility, mouth, eye, and skin care, infection control, requirements for safe transfer, and care of the dying patient.