The word “durable” before power of attorney means that the authority granted in a power of attorney will continue even if and when the principal no longer has mental capacity. With a nondurable power of attorney, the authority would cease if the principal became incapacitated. A power of attorney is a legal document that allows one person (known as the “principal”) to appoint another person (known as the “agent”) to act on his or her behalf for financial and legal matters. New York State has a statutory form that governs the format and requirements of a power of attorney form which includes a list of actions that the agent can take on behalf of the principal, such as finance, business, tax, insurance and real estate matters.