Using full-motion video, the architects and the DCS staff jointly "walked through" a televised tour of each building early in the planning process. Staff members and architects climbed virtual stairs and looked into virtual inmate rooms. Control stations were modeled and remodeled, and officers' lines-of-sight were carefully adjusted. Sallyports were laid out and revised. Privacy and security issues were viewed and reviewed. Together, designers and corrections staff explored the physical as well as the functional implications of many design alternatives without having to resort to expensive, full-scale mock-ups. As the end product of a series of interrelated computer programs, the 3-D videos' underlying structure was eventually incorporated into final working drawings that were used for bidding and construction. Computer technology was adapted in different ways to address each of DCS's three projects, because the programmatic needs of each building presented a different challenge. The use of the technology is described for an 80-bed maximum-security unit, a 200-bed minimum/community custody facility, and a 156-bed minimum-security dormitory.