he has been working mostly on various aspects of renal and intestinal phosphate transport, (endocrine) regulation of phosphate homeostasis, impact of phosphate on health and disease processes, and genetics of phosphate balance as well as on renal regulation of systemic acid-base homeostasis, renal and extrarenal sensing of acid-base equivalents, and the role of acids in disease. He is also co-leader of the Swiss Kidney Stone Cohort, chair of the Scientific Advisory Board of the European Renal Association (ERA) and board member of the European Association of Urology-Section of Urolithiasis (EULIS).