Proxy consent is the process by which people with the legal right to consent to medical treatment for themselves or for a minor or a ward delegate that right to another person. There are three fundamental constraints on this delegation:

1. The person making the delegation must have the right to consent.

2. The person must be legally and medically competent to delegate the right to consent.

3. The right to consent must be delegated to a legally and medically competent adult.

There are two types of proxy consent for adults. The first, the power of attorney to consent to medical care, is usually used by patients who want medical care but are concerned about who will consent if they are rendered temporarily incompetent by the medical care. A power of attorney to consent to medical care delegates the right to consent to a specific person. The second type is the living will.