Twenty years ago, Dr. med. Hans-Kaspar Schwyzer began systematically documenting shoulder prosthesis surgeries at the Schulthess Klinik. Thousands of cases later, this amount of data now provides unique insights for research and treatment. Together with his successor, Prof. Dr. med. Markus Scheibel, who now continues the project with his team, Hans-Kaspar Schwyzer reflects in this interview on the early days, the development, and the years of collaboration.