This paper highlights research into the improved effectiveness shopper insights can bring to social marketing programmes. By targeting known customers through their purchase history and identifying those active and influential in social media, brands can encourage greater levels of advocacy and generate a substantial and long-sustaining lift in sales. The study shows that targeting social marketing campaigns through household-level behavioural data generates more quality advocacy than using demographic or social influence data alone. Advocacy programmes that leverage both shopper and social data drive significant additional purchases of a brand in-store, increasing sales on average by 8 per cent. This sales lift sustains at an average of 4 per cent for 6 months after each programme ends, thanks to residual discussions and the lasting impact of personal recommendations.