Service-oriented architectures (SOAs) are a commonly used paradigm for IT infrastructures in various fields. Due to their flexibility and the easy accessibility of their underlying web services, SOAs are the architecture of choice for more and more service providers. Semantic SOAs (SSOAs) are going one step further and are enhancing the common SOA with semantic components. However, a major success criterion of any SOA is the existence of a reliant security infrastructure. Therefore, this paper identifies security requirements for an eGovernment SSOA focusing on communication security, trust, privacy and access control. Our work is based on the architecture designed within the scope of the European research project Access-eGov, which envisions the development of a SSOAbased eGovernment platform.