Biocybernetic adaptation is a new approach to optimizing human–computer interfaces and human–computer interaction. Bio-signals and, more broadly, vital data of a person are collected and interpreted in real time by a computer in order to trigger its own adaptive processes. The collection of highly sensitive data is thus a necessary condition for the purpose of making the application more user-friendly. Therefore, the most obvious and important social, legal and ethical issues in this kind of application are privacy and data protection. In this research note we report from a technology assessment project for the European Parliament. We provide some conceptual distinctions, highlight the most promising application fields, and discuss privacy challenges and potential regulatory actions to be taken.