Making treatment decisions for older people is difficult, because of the complex interplay of their multiple co-morbidities, but also because of the fine balance of risks vs. benefit in any chosen management plan. This becomes even more difficult when they lose the capacity to tell us what they want, and often in such situations we have to rely on information from others in order to make decisions based on their best interests. Advance care planning should help with making these decisions clearer, based on the documented preferences of what the patient would have wanted while capacity was still present. However, such documents are still very rarely used, and even if they are, health-care professionals are often wary of them for the multitude of ethical and legal problems that can arise.