The last three decades have seen major advances in oncology. As an active researcher I have been at the forefront of the development and implementation of the changes which included new laboratory tests, the development and implementation of novel radiotherapy technology, technical and clinical evaluation of new techniques of radiotherapy including an interest in late side effects of treatment, systematic reviews of radiotherapy technologies, testing new systemic therapies and developing new methods of care. The dissertation includes the principal work published in peer reviewed literature. While each publication tells an independent story they are linked in a narrative in the initial pages of the dissertation to summarise the critical aspects of each publication and define the context within oncology. The aim has been to generate objective and rigorous research output free of commercial and other potential vested interests to provide sound evidence based framework for patient care and treatment. Optimum management approaches have been defined for a number of tumour types based on distillation of research led by me combined with a critical review of literature published at the time. The goal has always been to come up with treatment and care strategies of real benefit to patients to improve survival, tumour control or quality of life. As would be expected, research activity did not always result in improvement. For ultimate progress it is equally if not more important to discard ineffective treatments that do not live up to expectation not to mislead patients and to avoid research "blind alleys" which divert effort and funds. Many of the studies reported have stood the test of time either as initial reports heralding a change in practice or as benchmark studies of aspects of tumour management some of which are quoted in major oncology texts.