Neither the political debate nor the legal debate nor the engineering debate properly reflects upon the essential contestedness of the underlying concepts of privacy and data protection. Talking about privacy and data protection by design without clarifying what is meant by "privacy" or "data protection" misses the point as much as talking about "democracy by design" without specifying which concept of democracy—direct, representative or semi-direct, parliamentary or presidential, just to name a few—is meant. Without such clarification, one cannot reasonably expect that privacy or data protection built into technical systems meets one's own expectations, those of the lawmaker of a particular law, the general public, or any other stakeholder, and will be accepted as being compliant with the applicable laws.