Integrative oncology (IO) is the term being increasingly adopted to embrace complementary and alternative medicine (CAM), but integrated with conventional cancer treatment as opposed to being considered a rival or true ‘‘alternative’’. Should ‘‘mainstream’’ oncologists take such developments seriously or dismiss them as eccentric unproven quackery? I think there are several reasons for encouraging cancer doctors to learn more about CAM, and to ultimately provide their patients an introduction and engagement with Integrative Oncology. The use of strategies now termed CAM is of course nothing new – the role of nutrition, herbal medicines, spiritualist approaches to healing have been practiced since ancient times. However in recent times far greater attention has been paid to CAM – especially in relationship to cancer. This is largely due to the relatively poor results of treating cancer with conventional modalities, the toxicity associated with the latter, and an increasing wish within society at large for patients to contribute to (even control) their own treatment. In some settings this has been interpreted as a challenge to doctors’ knowledge and authority resulting in an undesirable polarity distancing the patient from their professional careers. There are three good reasons for encouraging discussion about the concept of Integrative Oncology.