In the second half of the twentieth century, the clinical management of patients suffering pain from advanced cancer was transformed. This paper describes cancer pain management during this period, identifying three key elements that promoted innovation: First, the development of a patient-centered approach to analgesic evaluation, which resulted from the search for an alternative analgesic to morphine in studies led by Raymond Houde. Second, the re-introduction by John Bonica of the idea that pain is what the individual feels and thinks it is. Third, the work of Cicely Saunders in establishing the foundations of the modern hospice and palliative care movement. The work of these three clinicians must be set in the context of a time when new hopes emerged that cancer could be cured and, at the same time, the cancer patient began to be remolded from a passive participant in treatment and care to an active collaborator.