Deliverable D1.3 builds upon the cross-disciplinary perspectives of the AEC industry discussed in D1.1and D1.2, by providing a more detailed description of the prerequisites for multidisciplinaryinformation exchange and collaborative design platform functionalities that must be implemented toachieve PrismArch.The topics cover the general usability guidelines (Section 1), technical requirements for howmultidisciplinary data should be managed inside PrismArch (Sections 2), and user-orientedrequirements for data should be managed, visualised and interacted with inside PrismArch (Sections3-6).Section 2 begins by outlining the core data management requirements for multidisciplinary designand simulation. Various PrismArch-specific requirements that both enable and regulate the unifieddesign space are then described in detail.Section 3 describes the core functionality of the data management system inside PrismArch andoffers an analysis of information display methodologies aimed at arriving at the most efficient meansof representing metadata inside PrismArch.Section 4 looks holistically as the user scenarios established in D6.1 and the requirements for the VRexperience set out in Section 3 of D1.2, to arrive at the core functionality necessary to prove thePrismArch concept. The fundamental tasks and actions described in this section informs thePrismArch VR interface proposals in Section 5 and operational mock-ups in Section 6.