The Robert Koch Institute (RKI) regularly conducts nationally representative cross-sectional studies (KiGGS, DEGS and GEDA) as part of the nationwide health monitoring system. In addition to these health surveys, data is collected in telephone interviews either on specific thematic fields (such as diabetes) or specific groups (such as medical staff) that were not or only insufficiently covered by the larger health surveys. As they are flexible and fast, ad hoc surveys conducted via telephone interviews can respond to specific epidemiological and health political questions. This article describes the procedures applied in ad hoc telephone interview surveys, which were newly introduced as a standardised method in 2017 and are applied by the Laboratory for Health Surveys at the RKI. The article presents the stages of project management such as concept development, establishment of a concept for data protection, questionnaire development, pre-test and field phase, calculation of weighting factors and provision of the final data set. The aim is to describe the process and shed light on the standardised procedures, the reported quality indicators and the breadth of possible scenarios of application.