Two short documents determine what happens to a person's money and body if they cannot speak for themselves, and most people either do not have them or have versions that will not work when needed. This article explains what a durable power of attorney and a health care directive actually do, why the word "durable" is the entire point, and why the alternative — a court-supervised guardianship — is slower, more expensive, more public, and less faithful to what the person would have wanted. It works the agent's authority and its limits, the hot powers that must be expressly granted, the fiduciary duties an agent owes, and the practical problem that dominates this field: financial institutions refusing to accept valid instruments. On the health care side it covers the constitutional foundation from Quinlan through Cruzan, the difference between an advance directive and a portable medical order, the substituted-judgment and best-interests standards, and the HIPAA authorization without which an agent cannot obtain the information needed to decide anything. The final sections address capacity, revocation, financial exploitation by agents, and the sequencing that determines whether these documents work at the moment they are needed.