One of the major challenges in the development, validation and deployment of autonomous vehicles is to understand what constitutes their correct behavior. The behavior specifications of autonomous vehicles come from numerous sources, including not only the vaguely written traffic laws, but also ethics and local driving culture to ensure their predictability and compatibility with other traffic participants. In this talk, I will provide real-life examples where such specifications are conflicting and present a new formalism called “rulebooks”, developed at Nutonomy, to specify the correct behavior of autonomous vehicles and provide a systematic approach to handle possibly conflicting specifications.