Prof. Dr.-Ing. habil. Volkmar Zabel is a civil engineer specializing in the fields of structural dynamics and system identification. His research work always focuses on methods for recording and evaluating the condition of existing structures and mapping them in numerical models. Procedures based on the identification of dynamic system behavior play a major role here. The detection and handling of uncertainties in the results obtained with these methods lead to questions in the current research activities within the working group.