Image from Bernd Helfert
In architecture, or in hab, ecological, or information system design, the attempt to accommodate as many different sorts of sophonts within the same structure. This design philosophy goes all the way back to Old Earth's Information Age, when architects started to create public buildings usable and accessible to all varieties of human baseline, including those who might be deaf, blind or colour blind, dependent on wheelchairs or walkers, carrying infants, and so on. By the close of the Nanotech Age this movement had expanded into an attempt to meet the needs of the small but rapidly growing groups of nonhuman and posthuman sophonts as well. Though interest in the concept died in the fragmentation of the Age of the Technocalypse, the dawn of the Interstellar Era saw renewed interest. Support for Universal Design principles was strong in the First Federation, as a part of its strategy to promote strong cross clade and cross-cultural linkages. In the time since some multi clade polities have arisen that might be impossible without Universal Design principles.
Universal Design is heavily dependent on multi purpose structures and devices, or on environments that reconfigure themselves on short notice. A hab built according to Universal Design principles can meet the needs of an astonishing array of sophont clades. It displays information in ways that are compatible with a variety of sensory and cognitive ranges and provides a physically and psychologically comfortable physical setting for beings with a great variety physiques and environmental requirements. Even with a complete suite of sophisticated strategies and high technologies, though, Universal Design does have limits. Beyond those limits, clades that wish to interact must use envirosuits, or use virch or eidolon or other telepresence strategies.
The antithesis and rival of Universal Design is Clade Patternism, a design philosophy that seeks to produce an extraordinarily attractive and comfortable environment tuned to a single clade or species, or even to members of a particular culture within that group. Naturally there are those who have attempted a synthesis of the two philosophies, sometimes with an astounding degree of success.