Again, your friend needs to consult the law in her area to determine exactly what requirements are needed to set the document into effect. The document is likely to say that it comes into effect when your friend becomes incapable of making certain decisions. She can specify the people who she wishes to make that decision, for example, two physicians.

The law may also define exactly what is deemed to be incapacity to make decisions. For example, the Personal Directives Act of Alberta describes capacity as the ability to understand information that is relevant to making a personal decision with the competence to appreciate the reasonable foreseeable consequences of the decision.