The purpose of this case study was to explore the effectiveness of an individualized, strengths-based coaching approach with an elite cricketer, when compared to two control participants. The coaching consisted of four meetings that occurred over a one month period at the start of the cricket season. Multisource ratings (i.e., self, coaches, teammates) of mental toughness were obtained at baseline, intervention, and post- season. Visual analysis of data revealed general improvements in raw scores of multisource ratings of mental toughness for the experimental participant, with relatively stable levels of mental toughness indicated for the two control participants. Reliable changes in attentional control and self-belief facets were evidenced according to our statistical criterion. This case study has provided initial evidence for the effectiveness of an individualized, strengths-based coaching approach to develop facets of mental toughness, and supports the need for further evaluative research on positive psychology interventions in sport contexts.