This paper looks at the Internet and the changing set of requirements for the Internet that are 8oriented towards the consumer, and used for a wider set of purposes. We discuss a set of principles that have guided the design of the Internet, called the end to end arguments, and we conclude that there is a risk that the range of new requirements now emerging could have the consequence of compromising the Internet?s original design principles. Were this to happen, the Internet might lose some of its key features, in particular its ability to support new and unanticipated applications. We link this possible outcome to a number of trends: the rise of new stakeholders in the Internet, in particular Internet Service Providers; new government interests; the changing motivations of the growing user base; and the tension between the demand for trustworthy overall operation and the inability to trust the behavior of individual users.