Rick Haas is a soft tissue sarcoma focused radiation-oncologist from the NKI-AVL in Amsterdam, the Netherlands, where he is employed now for more than 25 years. Since January 2017, he is also appointed at the Leiden University Medical Center, the Netherlands. He is an active member of CTOS (Board of Directors 2015-2017), the EORTC-STBSG (President of the Local Treatment Subcommittee), and the Sarcoma Patients Euronet (SPAEN) Patient Advocacy Organization (Medical Advisory Board). He initiated several sarcoma related clinical trials in phase I (NCT01985295), phase II (NCT02575066, NCT02106312) and phase III (NCT01344018). He also initiated several preclinical research projects into sarcoma radiobiology and patient derived xenograft models.