WH got a degree in Biochemistry from the ETHZ. Thereafter he moved to the University of Bern for a PhD in Neurobiology (Prof. N. Herschkowitz). After a postdoc at the University of Georgia in Athens/GA (Prof. D. DerVartanian), he joined the Institute of Pathophysiology, headed by Prof. H. Fleisch. There, WH started to work on the biology of skeletal tissues. In 1997, WH joined the Department Clinical Research at the University, where he heads the Group of Bone Biology & Orthiopaedic Research.