An enduring guardian has the legal right to make most substitute decisions for a person with mental incapacity as if the guardian were that person. Where possible an enduring guardian should consider what decision the person would make in the situation if capable.

The types of decisions an enduring guardian might have to make include:

Where a person has appointed an enduring guardian, and also appoints a medical agent (under the Consent to Medical Treatment and Palliative Care Act 1995 ), both have the power to make decisions concerning medical treatment. It is not necessary to have both. The enduring guardian cannot act in relation to medical treatment if the medical agent is available and willing to act - Guardianship and Administration Act 1993 s 25(5)(b). In addition, the person may also have completed an anticipatory direction and the enduring guardian cannot act inconsistently with this direction, see who can consent.

Additional authority may be necessary if an enduring guardian needs to override the refusal of the person for whom they have been appointed. This situation could occur if the person for whom they have been appointed is refusing to move residence or to have necessary treatment, and by doing so, is putting either their own health or safety, or the health or safety of others at risk. If an enduring guardian requires special powers to authorise physical compulsion, he or she must apply to the Guardianship Board for an order granting powers under the Guardianship and Administration Act 1993 s 32. For further details regarding these powers and how to apply contact the Office of the Public Advocate.