The aim of this study is to close the gap between the theory of market orientation and the practice of implementation by determining the critical success factors of one company’s approach, namely De Beers’ ‘Supplier of Choice’, for use by other corporates in similar contexts.The research was undertaken as a single, explanatory case study to gain an understanding of the specifics of De Beers’ approach to market orientation, and was a longitudinal study over a 10 year period. It was completed in two stages, with phase one being qualitative, and comprising documentary research. This was supplemented by a second qualitative phase of three personal, in-depth, and semistructured interviews. Several different sources of data were used to triangulate corroboration of the findings. Implementation occurred in steps which concentrated on communicating top managements’ vision throughout the organisation using internal publicity and operationalising the objectives, improving the interdepartmental effectiveness of key divisions, and finally by redesigning the performance management system using market-based rewards. The theoretical elements of Kohli and Jaworski’s (1990) model are applicable to defining the practice of implementing this type of strategy. Two discrepancies exist between theory and practice. Firstly, that communication of the vision can be on a ‘need to know basis’, and secondly, across the board market-based reward systems are not critical to managing performance during implementation.