There is currently a gap between engineering practices of system architecture and software architecture, and this can and does cause many problems in the development and acquisition of large-scale software-intensive systems in the DoD. Systems-of-systems (SoS) are particularly susceptible to major disconnects between system and software architectures. The SoS depends on the system architecture to guide the development of the individual systems and the concept of operations (CONOPS), and is also dependent on the software architecture allowing interoperation between nodes, and the sharing of critical timely information. All programs must find a way of matching the system architecture to the software architecture, handling the inevitable development parallelism, and ensuring that the system architects, software architects, and CONOPS developers interact appropriately to get the best possible system. This working session will be a facilitated forum to begin to capture the current state of practice for integrating system and software architectures. We also want to begin to identify the architecture integration gaps and technical obstacles.