To develop these guidelines, three questions will be answered. The first question is how differentiation is currently operationalized within European consumer law. The answer to this question not only indicates how one-size-fits-all European consumer law is right now, but also what methods are currently used for the operationalization of differentiation. The second question is in what other ways differentiation could potentially be operationalized. To improve differentiation, more statuses could be recognized, like that of the prosumer. But there are probably also other valuable ways in which differentiation could be improved, like introducing more standards, focusing more on the characteristics of a transaction, and using big data analytics and machine learning to personalize law. The third question that will be asked as part of this subproject is what exactly can be gained by more differentiation and what can be lost. More differentiation can reduce the under- and over-inclusiveness of European consumer law, but more differentiation probably also comes at a cost.