The paper investigates the evolution from corporate social responsibility to supply chain responsibility via the examination of a leading UK food retailer. These two concepts differ substantially and illustrate contrasting approaches in terms of social responsibility development and application. A qualitative case study methodology is used where managers from that leading retailer and its suppliers, industry experts and representatives from professional bodies are interviewed. An observation of an ethical audit with a retailer’s supplier was also conducted. Findings show an example of good practice in the area of corporate social responsibility in the supply chain and illustrate the substantive progress that can be made in achieving supply chain responsibility. At the same time, the paper provides the specific challenges in developing from a corporate social watchdog approach to one in which the power in the chain is more balanced and where a holistic approach requires to be taken to social responsibility. Considering the scarcity of work examining empirically the issue of corporate social responsibility in food supply chains, this study demonstrates an evolutionary process and its stages based on an examination of the food retailer’s supply chain and the corporate social responsibility approach it has taken with its suppliers. We also illustrate a range of key implications that need to be considered by both managers and policy makers and we provide a range of areas where further research is required.