Abstract: This paper describes the OpenVCE system, which is an open-source environment that integrates Web 2.0 technology and a 3D virtual world space to support collaborative work, specifically in large-scale emergency response scenarios, where the system has been evaluated. The support is achieved through procedural knowledge that is available to the system. OpenVCE supports the distributed knowledge engineering of procedural knowledge in a semi-formal framework based on a wiki. For the formal aspect it relies on a representation used in AI planning, specifically, Hierarchical Task Networks, which corresponds naturally to the way emergency response procedures are described in existing Standard Operating Procedures. Knowledge engineering is supported by domain analysis that may highlight issues with the representation. The main contribution of this paper lies in a reasonably informal description of the analysis. The procedural knowledge available to OpenVCE can be utilized in the environment through plans generated by a planner and given to the users as intelligent, distributed to-do lists. The system has been evaluated in experiments using emergency response experts, and it was shown that procedural uncertainty could be improved, despite the complex and new technologies involved. Furthermore, the support for knowledge engineering through domain analysis has been evaluated using several domains from the International Planning Competition, and it was possible to bring out some issues with these examples.