A primary goal of vehicular communication systems is the enhancement of traffic safety by equipping vehicles with wireless communication units to facilitate cooperative awareness. Privacy issues arise from the frequent broadcasting of real-time positioning information. Thus privacy protection becomes a key factor for enabling widespread deployment. At the same time, stakeholders demand accountability due to the safety-critical nature of many applications. Earlier works on privacy requirements for vehicular networks often discussed them as a part of security. Therefore many aspects of privacy requirements have been overlooked. In this paper, we identify a structured and comprehensive set of privacy-related requirements for vehicular communication systems, andanalyze the complex inter-relations among them. Our results enable system designers to better understand privacy issues in vehicular networks and properly address privacy requirements during the system design process. We further show that our requirements set facilitates the comparison and evaluation of different privacy approaches for vehicular communication systems.