Critical case sampling is a type of purposive sampling technique that is particularly useful in exploratory qualitative research, research with limited resources, as well as research where a single case (or small number of cases) can be decisive in explaining the phenomenon of interest. It is this decisive aspect of critical case sampling that is arguably the most important. To know if a case is decisive, think about the following statements: ?If it happens there, it will happen anywhere?; or ?if it doesn?t happen there, it won?t happen anywhere?; and ?If that group is having problems, then we can be sure all the groups are having problems? (Patton, 202, p.237). Whilst such critical cases should not be used to make statistical generalisations, it can be argued that they can help in making logical generalisations. However, such logical generalisations should be made carefully.