levels describe the interrelated configurations of physical elements and decision clusters that occur within a larger dependency hierarchy. In Open Building terms, the Support constitutes a higher level, while infill is lower, dependent level: should the Support change, the infill is inevitably affected, although the infill can change without forcing change at the higher Support level. Environmental levels include: the urban (tissue) level; Support (base building or building) level; infill (fit-out) level; and furniture (furnishings) level. by Prof. Dr. Stephen Kendall, Building Futures Institute, Ball State University