The study analyses the question, of how irregular migrants who are not in contact with the authorities can be reached to provide them with information on voluntary return. After a presentation of the relevant provisions of Austrian law, the study focuses on the relevant groups of irregular migrants and the actors involved in disseminating information on voluntary return. A specific focus is placed on the tools used to disseminate information and related challenges are also analysed. The study closes with a chapter on statistical data and estimates of irregular migration in Austria and a summary of the major findings.