Thomas “Rock” MACKIE is Professor Emeritus of Medical Physics and Human Oncology at the University of Wisconsin (UW) and serial entrepreneur who has co-founded many not-for-profit and for-profit organizations. He was a professor of medical physics for 25 at the UW and supervised the PhDs of more than 40 students. In 1992, he co-founded Geometrics Corporation to develop the Pinnacle radiotherapy treatment planning system (TPS) based on 3D CT scans and once the largest selling TPS in the world. In 1997, Rock co-founded TomoTherapy, and was its Chairman of the Board from founding to IPO and on to sale to Accuray Corporation in 2011. Rock was also awarded the AAPM Coolidge Award in 2014 and the ASTRO Gold Medal in 2019. He is a co-founder and Chairman of the Board of several companies including Leo Cancer Care, a company developing technologies to improve proton beam access and radiotherapy accuracy as well as HealthMyne, a company mining data from medical images now owned by Roche. He is a Commissioner and Vice-Chair of the ICRU.