Big data has become a buzzword and has been one of the most sought after topics for research. The applications of big data have been studied in various important contexts. However, very little has been explored in the realm of integrating knowledge co-creation with the usage of big data when it comes to evidence-based decision-making. The current study empirically investigates data from four fashion retailing organizations. Evidence from our findings suggests that knowledge-based interactions between the customers and the salesforce in those organizations form the core of knowledge co-creation. The findings have revealed that big data indeed can assist in knowledge co-creation, which can in turn adequately lead to evidence-based, effective and efficient decision making for better business returns.