In simple terms, the principles of beneficence, non-maleficence, autonomy and justice sub-consciously influence most of our decisions in medical practice.

Next, we need to know whether the patient has the capacity to make informed decision.  When the patient cannot make decisions then someone else must do so. Traditionally, doctors and family members have made decisions on behalf of the patients. However, in recent years the role of enduring power of attorney for health care and advanced treatment directives has increased. Through these legal concepts, the patient's wishes will be honoured. This means the standard for substituted judgement was decided by the patient. When the patient's wishes are not known then a best interest standard is used. Both substituted judgement and best interest have been subject to criticism. Recent trend is that the pivotal role of the family in making decisions is favoured.

Questions regarding what is, and what is not appropriate therapy often arise in palliative care. There are two guiding principles here. First, at least in some circumstances it is futile to treat or to prolong treatment. The principles of justice and equity suggest that the common good has precedence over the individual needs.

The second guiding principle is whether the treatment should be directed to prolong life or whether the therapy should be used to relieve suffering.  Whether or not it is appropriate to offer or withhold or withdraw a particular treatment depends on the balance between the potential benefits and and the possible burdens and the risks of that particular treatment. Assessment of the appropriateness will depend on individual circumstances and is often difficult and complex.