Background: The DNA damage response (DDR) is a specialised stress response fundamental to maintaining genome integrity and suppressing tumour formation. Traditional molecular and cellular biology, combined with genetics and biochemistry, have led to an understanding of the architecture of the DDR in a variety of model organisms and in human cells. These studies have employed populations of cells/molecules and their results are of necessity an average of the response. High sensitivity imaging technologies make it feasible to study events in single cells and to do experiments with small numbers of molecules in vitro. These can now be applied to the DDR. Project Objectives: To provide an interdisciplinary training in single cell and single molecule studies to graduate students in Physics, Chemistry, LS, Maths and Computer sciences. The focus of the research will be the study of the DDR and genome stability. The main technologies to be developed concern high resolution molecular imaging methodologies. Specific aims: To train eight early stage researchers to doctoral level to utilize an interdisciplinary approach to address specific scientific questions and to communicate between disciplines. Study Design: We will achieve our objective by building a network comprising four “local” groups, each a collaboration between an imaging specialist and a cell biologist / molecular geneticists engaged in research on genome stability. The collaborating scientists will serve as co-advisors and will develop a personalised interdisciplinary research training programme for each recruit. Local training will be augmented by specially designed network-wide summer schools, workshops and meetings encompassing all network participants and invited experts. An industrial partner is integral to the network in order to share methods and provide secondments and input into workshops to train researchers in technology exploitation.