In elite sport, the advantages demonstrated by expert performers over novices are sometimes due in part to their superior physical fitness or to their greater technical precision in executing specialist motor skills. Since the cognitive revolution, mainstream psychologists have been increasingly cautious about the utility of verbal reports of cognitive processes. The chapter focuses on questions about methods for measuring or more accurately assessing expert knowledge, in particular addressing a wider range of methods to help us understand what experts know. Qualitative research is particularly useful in breaking new ground where there is not yet an established body of knowledge or existing theoretical models of the phenomenon of interest, or where there are as yet few existing findings to generate nuanced and specific hypotheses. In an area that is already rippling with insightful research designs to capture features of a dynamically unfolding and highly contingent set of skills, it is hard to suggest that there might be supplementary methods.