Power of attorney
A legal document that lets someone you choose, called an agent, make financial or health decisions for you.
A durable financial power of attorney stays in effect if you can no longer make decisions yourself, which is why it matters for aging parents. A separate health care power of attorney covers medical decisions.
The agent must act in your interest, keep your money separate from their own and keep records. Rules differ by state, so the document is usually drafted to match your state's law.