Max van Essen, University of Oxford, Oxford, UK, discusses the creation of an organoid derived from induced pluripotent stem cells (iPSCs) to study Shh (Sonic Hedgehog)-medulloblastoma, the most commonly occurring variant of brain tumors in infants. As iPSCs have the ability to differentiate into any cell type, cerebellar development can be examined, and an in vivo model to study medulloblastoma was successfully developed with the introduction of a PTCH1 mutation. This interview took place at the British Neuro-Oncology Society (BNOS) Annual Meeting 2022.