was Professor of History of Art at Berlin University of the Arts from 1980 to 1999. His doctoral thesis, completed at the University of Münster, was awarded the Alfred Töpfer F.V.S. Foundation award. He was a scholarship-holder at the Max Planck Institute in the Bibliotheca Hertziana in Rome and a research assistant at the Ruhr University of Bochum, where he completed his ›Habilitation‹ qualification on Andrea Pozzo. He subsequently worked as a professor and member of the Academic Council in Bochum. His research focuses on American art since 1945, European art of the 20th century, Andrea Pozzo, and the Roman art of the Seicento, particularly Gianfrancesco Romanelli.