With an advance directive, people can make provisions for the case of incapacity to give consent with regard to future medical and nursing treatment decisions. Currently, there are no data available on how well known and widespread advance directives are in the population in Germany. The aim of the study was, in addition to record awareness and dissemination, to find out more about the reasons for (not) writing an advance directive and about information and support used by people. An online survey of a representative sample of the general population (n=1000) was conducted. The data were analysed descriptively and by means of regression analysis. The survey showed that 92% of the sample knew about advance directives, and 37% had already created one. The probability of having already written an advance directive increases with increasing age. The reported reasons for (not) writing were heterogeneous. Almost 2/3 of all respondents had already accessed information on this topic, mainly via the Internet. The majority of those surveyed was not aware of any support available in drafting the advance directive. These findings provide suggestions for tailoring information and support services.