Next to surgery, radiotherapy and chemotherapy are the two most commonly applied treatments against cancer. These therapies are often combined, but the therapeutic outcome is still limited. Nanocarriers may be the solution to many of the issues encountered when combining these therapies. In this review, the role of nanocarriers in combined radiotherapy and chemical cancer treatment is discussed, divided into four distinct strategy classes. For each strategy, examples of the literature are given to come eventually to conclusion on the possible translation to the clinic.