200,000 voluntary coaches ensure that the large investments in sports facilities in the UK are effectively used and that the athletes experience a healthy life. In a socioeconomic period in which volunteering may be diminishing, more coaches to successfully implement the national strategy for sport. Yet very little is known about how individuals, in particular parents, decide to become voluntary coaches. The research set out to test if a quantitative model could represent such a decision process. It formulates a model of the process and tests the model against field data. From Social Exchange Theory, a conceptual model was developed of the decision process to enter a coach education programme. It was clear that the process was multi-dimensional. The research then showed how this multi-dimensional conceptual model could be mathematically represented by a logistic regression model. Published work on volunteering, sport and coaching was reviewed. From this literature review, a set of potential explanatory variables was obtained which previous researchers had suggested to be involved in decision processes involving volunteering and coaching. Hypotheses were made for these potential explanatory variables. Data was collected by personal interview of a sample of 112 individuals associated with athletics in the UK. The sample was taken from qualified, voluntary athletic coaches, from adult members of two amateur athletic clubs, and from parents of children in these clubs. The building of the logistic regression model showed the relative importance of each of the explanatory variables to the decision process. It also showed whether or not variables were independent or associated with another variable. Tests were conducted to indicate how well the mathematical model fitted the data and, hence, how well the conceptual model represented the sample. The use of logistic regression allowed the potential explanatory variables to be ranked in order of influence on the decision to become a coach. It also allowed the hypotheses to be tested. Qualitative information was also obtained from the interviews. These allowed the logistic regression model to be triangulated. The qualitative data gave further insights into the perceptions of adults, especially parents, and of coaches. It also indicated the key events which triggered a decision to coach. The logistic regression model provided a satisfactory fit to the data indicating the adequacy of the conceptual model. It indicates that the two genders have differing sets of significant explanatory variables. Some variables were found to be more complex than suggested by the published literature, others to be non linear and some not significant. The degree of fit suggested that one or more unknown, but significant, variables still need to be identified. The research suggests how the models could be improved and developed. There are implications for the future recruitment, training and retention of voluntary athletic coaches. By extension, the conceptual and mathematical models can be adapted for other adult education decision processes where the choice of course is voluntary.