The article analyses the three terms autonomy, dignity and vulnerability. The relevance and practical application of the terms is tested in two spheres. First, as guiding principles in the area of ethics of medicines and science. Second, as human rights principles, serving to guide the conduct of public policies for an effective realization of human rights. The article argues that all human beings have the same dignity, but that the autonomy--and therefore vulnerability--differs considerably. Simply said, with reduced autonomy comes increased vulnerability, implying extra attention to the protective dimensions. The article finds that the three terms approach the protection of human beings in different ways and that all are relevant and applicable in both spheres, but that an isolated notion of autonomy and a 'group-based' notion of vulnerability are not adequate.