Radiotherapy is an essential component of care for the most common cancers globally. Achieving equity in access is imperative - 80% of the world’s cancer patients are in low- and middle- income countries (LMICs), but have access to only 5% of global radiotherapy resources. By 2035, models suggest that 12 million patients per year in LMICs would benefit from radiotherapy. Investment in meeting radiotherapy needs has the potential to return USD 278.1 billion net in benefits and save 26.9 million life years for an investment of USD 184 billion. The cost of inadequately treated cancer had already reached USD 895 billion in 2010. The associated upfront costs of developing radiotherapy services are expected to be recouped within 10-15 years in LMICs.