The introduction sets the scene for the Special Issue by describing how digital online market places through their contract based business models to a large extent in reality evade state regulation on e.g., consumer protection and labour law rights. They replace this regulation with their own private governance systems that regulate issues that are often of broad societal interest such as product safety, workers’ rights and issues of discrimination. Contrary to what one might expect, it is observed that these private governance systems often fully live up to consumer protection laws and sometimes even go further than state regulation in order to please the customers. It is observed that the downside of this is what could be called ‘balloon effects’ in other areas of the law. Thus, ‘over compliance’ with regard to consumer protection often leads to ‘under compliance’ in other areas of the law. In the introductory article, it is explained how all the contributions address such ‘balloon effects’ in a private law perspective.