OpenBuildings Designer (formerly AECOsim Building Designer), Bentley’s multi-discipline building information modeling (BIM). Explore, design, and deliver innovative buildings faster. Design, analyze, document, and visualize buildings of any size, form, and complexity. Effectively communicate design intent and bridge barriers between building disciplines and geographically distributed teams. OpenBuildings Designer (formerly AECOsim Building Designer) provides building information modeling (BIM) advancements so you can deliver buildings faster and with greater confidence – confidence in your design, workflow, capabilities, and deliverables. Increase collaboration among architects, mechanical, electrical, and structural engineers with a shared set of tools and workflows. Integrate information you have from multiple formats and easily work on projects of any size. Clearly communicate your design intent with reliable deliverables that you can easily customize.