Service-oriented architectures (SOA) are being adopted in a variety of industries. Some of them must support real-time activities. In this article, the authors present RT-Llama, a novel architecture for real-time SOA to support predictability in business processes. Upon receiving a user-requested process and deadline, our proposed architecture can reserve resources in advance for each service in the process to ensure it meets its end-to-end deadline. The architecture contains global resource management and business process composition components. They also create a real-time enterprise middleware that manages utilization of local resources by using efficient data structures and handles service requests via reserved CPU bandwidth. They demonstrate that RT-Llama’s reservation components are both effective and adaptable to dynamic real-time environments.