Qualitative theories of illness experience are about the individual interpretations of the psychosocial and cultural aspects of living with illness. Thus, they contribute to a better understanding of health and health care provision. In this paper, we examine how a grounded theory (GT) of heart disease experience can inform secondary prevention. In-depth interviews of individual experience of heart disease were conducted with 26 patients, using GT iterative data collection and analysis framework. A GT was compiled from data and examined within a sociocultural framework to ascertain how experience influenced health behaviour. Despite individual contextual variations, the theory of 'keeping it going' describes the study sample's common attitude to living with heart disease. The theory was adequate in explaining secondary cardiac behaviour, because it identified the aspects of patients' beliefs and attitudes which are key to effective secondary prevention. The assessment of the impact of illness experience on health behaviour within a sociocultural framework helped to articulate the strong influence of social and contextual factors. The study offers an appropriate explanatory framework for encouraging health behaviour change. It emphasizes the importance of interventions being relevant to individual perceptions and interpretations. It provides a framework for designing and evaluating cardiac interventions and the theoretical principles which underpin them.