Advance care planning (ACP) is promoted as beneficial practice internationally. This article critically examines different ways of understanding and measuring success in ACP. It has been 50 years since Luis Kutner first published his original idea of the Living Will, which was thought to be a contract between health carers and patients to provide for instructions about treatment choices in cases of mental incapacity. Its purpose was to extend a patient's right to autonomy and protect health carers from charges of wrong-doing. Yet, it can be doubtful whether different types of ACP achieve these goals rather than aiming at secondary gains. My discussion suggests that the current promotion of ACP is not always engaging critically with the original ACP intentions and may even pursue notions of success that may run contrary to respecting autonomy. The risk of this may especially be the case when high participation rates are taken as indicators of success for institutional ACP programs. I further suggest that Kutner's two original aims of protecting patient autonomy and preventing charges of wrong-doing are near impossible to achieve in conjunction, because their simultaneous pursuit fails to acknowledge that patients and carers have opposing needs for reassurance about possible judgment errors. I conclude that the most realistic idea of success of modern ACP is an acknowledgement of the importance of ongoing dialogue about what constitutes appropriate care and a diversity of aims rather than any kind of advance, contractual insurance in the face of controversy.