The diagnostic technology in modern medicine is providing increasingly detailed information on the potential progress of health or of a disease. Those concerned are confronted with the task of anticipating the significance of the probability of occurrence in each case for the potential way of living their own lives and to make concrete decisions regarding examinations or treatment in each individual case. Using prenatal diagnosis as an example, Gabriela Brahier studies how the women concerned reach their decision based on the test. Based on a philosophically and socially informed theology and a qualitative case study, the author shows that the decisions are made on the basis of synthesizing strategies which are geared towards the idea of authenticity, and that this has far-reaching consequences for the concept of personal autonomy and for genetic counseling as well.