The demand for medical services such as critical care is likely to often exceed supply. In the setting of these constraining conditions, institutions and individual providers of critical care must use some moral framework for distributing the available resources efficiently and equitably. Guidelines are therefore provided for triage of critically ill patients. There are several general principles that should guide decision making: providers should advocate for patients; members of the provider team should collaborate; care must be restricted in an equitable system; decisions to give care should be based on expected benefit; mechanisms for alternative care should be planned; explicit policies should be written; prior public notification is necessary. Patients who are not expected to benefit from intensive care, such as those with imminently fatal illnesses or permanent unconsciousness, should not be placed in the intensive care unit. Hospitals should assign individuals the responsibility of intensive care triage, and a committee should oversee the performance of this responsibility to facilitate the most efficient and equitable use of intensive care.