You would need a will at least. But in addition to a will, that will determine who gets what, when, and how, and who are the decision makers when the time comes. You would also want to plan for things that might happen during your lifetime. A durable power of attorney that would take care of you if you became incapacitated is also a necessary document. In addition to that, you would want a living will and designation of healthcare surrogate so that your wishes with regard to healthcare are considered by your loved ones, and also you would be appointing someone to make final decisions for your healthcare if the time came.