The incidence of brain metastases is expected to increase because of better treatments of primary tumours. Novel diagnostic and therapeutic techniques are continuously being developed, all of which need thorough evaluation before they can be implemented in clinical routine. Randomized Controlled Trials are the gold standard to do so, but they have shown many challenges, especially when applied in a cancer setting. .The 'cohort multiple Randomized Controlled Trial (cmRCT)' design is a promising design for multiple (simultaneous) randomized evaluations of experimental interventions, with potential for increased recruitment, comparability and long-term outcomes as a standard. This design will speed up the process of translating treatment innovations to the daily clinic.