The Otto-Selz-Institute of Applied Psychology (OSI) (in German: Otto-Selz-Institut für Angewandte Psychologie) in Mannheim, Baden-Wuerttemberg, Germany is a psychological and interdisciplinary research institute and an associated institution within the University of Mannheim. Under the leadership of Prof. Dr. Georg W. Alpers, president of the Institute, and Prof. Dr. Sabine Matthäus, vice president of the institute, OSI employs a staff of about 20 researchers and additional support staff. The OSI was established in Mannheim in 1964 and is still headquartered there. The institute was named after the German pioneer of neuroscience and last director of the Handelshochschule Mannheim Otto Selz.