These two terms get used interchangeably so often that most people assume they mean the same thing. They do not. The difference matters, and once it is explained clearly, it is not complicated.
What a living will does
A living will, sometimes called a declaration as to medical or surgical treatment, is a document in which you state your wishes about end-of-life medical care. It addresses things like whether you want life-sustaining treatment if you are in a terminal condition with no reasonable chance of recovery, whether you want artificial nutrition and hydration, and whether you want CPR attempted. The living will speaks for you when you cannot speak for yourself. It is a statement of your values and preferences, not a delegation of authority to another person.
What a healthcare directive does
A healthcare directive, sometimes called a medical power of attorney or healthcare proxy, designates another person to make medical decisions on your behalf when you cannot make them yourself. Your healthcare agent can talk to your doctors, review your medical records, consent to or refuse treatment, and navigate decisions across a wide range of medical situations, not just end-of-life scenarios. The directive gives a real person the authority to respond to circumstances as they actually unfold, something a document written in advance can never fully do on its own.
Why both documents matter
A living will tells healthcare providers what you want in certain scenarios, but it has limits. It covers specific situations and cannot adapt when the facts on the ground are different from what the document anticipated. A healthcare agent, guided by your values and your living will, can interpret your intentions in real time and speak up on your behalf. The two documents work together. Relying on only one leaves gaps that your family will have to navigate under circumstances nobody wants to be improvising through.
Colorado's approach
Colorado combines these concepts in a single document called the Advance Directive for Medical/Surgical Treatment, which lets you name a healthcare agent and state your treatment wishes in one place. Colorado also recognizes a separate CPR Directive, particularly relevant for elderly individuals or those with serious illness, governing whether CPR should be attempted. These documents have specific legal requirements to be valid. A form downloaded from the internet may not meet them, and a form sitting in a drawer that your healthcare agent has never seen is not much better.
The conversation that has to happen
The paperwork is the easy part. The harder and more important thing is the conversation with your healthcare agent. The person you name needs to understand your values and your priorities well enough to make decisions the way you would make them. A document signed once and never discussed is better than nothing, but not by as much as people assume.
If you do not have these documents, or if the ones you have are old or were never talked through with the person named, that is worth fixing.