PSI CRO is a global full-service contract research organization (CRO), committed to being the best CRO in the world as measured by its employees, customers, investigators, and vendors. PSI’s key operational differentiator is on-time delivery of clinical trials. This metric remained above 90% in 2024.

The company specializes in pivotal phase 2 and phase 3 clinical trials in oncology, hematology, gastroenterology, autoimmune, infectious diseases, neurology, and other indications. PSI provides expertise in complex trials at the forefront of precision medicine, including platform and umbrella designs, trials in targeted immunotherapy, radiopharmaceuticals, and cell and gene therapies.

In 2025, PSI is celebrating its 30th year of business as the only fully independent and privately owned mid-sized CRO. PSI employs over 3,000 people across 56 countries as of December 31, 2024. Global headquarters are in Switzerland at 113a Baarerstrasse, Zug 6300.