Quality of cancer care is difficult to define and to evaluate. Here we consider three components represented by the questions: (i) Is the right question treatment being given? (ii) Is it being done well? and (iii) Is the patient being treated as well as the disease? Determining the right treatment requires a hierarchy of evidence from clinical trials, and high quality clinical trials to determine and supplement that evidence. Evidence-based guidelines are then useful in increasing compliance with evidence-based treatment. Quality of delivery of treatment is dependent on volume of practice: patients with rare or complex diseases should be referred to cancer centres. Treatment of the whole patient requires attention to communication, and to the management of symptoms such as pain and fatigue. Cancer care must be of high quality and delivered with compassion.