“Therapy resistance is one of the biggest problems currently facing clinical oncology. To better understand how resistance mechanisms develop during treatment, our group has developed a toolbox of molecular imaging agents to track this process in living subjects. Whilst tumours employ a myriad of different ways to evade death, we have focused our efforts on imaging common downstream pathways that are agnostic to the causal mechanisms. In this talk, I describe how imaging tumour antioxidant production holds great promise for treatment response monitoring and predicting resistance. I further describe the development of a novel radiotracer for cancer stem cell imaging in refractive disease. We have exploited the overexpression of these cancer-resistance biomarkers to create novel radionuclide and antibody-drug conjugate therapies. Now, we can not only detect treatment failure but will, in the future, be able to provide an effective treatment option for these patients.”