A highly unusual feature of PHIDIAS II is that it implements all of its functions using only hypermedia mechanisms. Complex vector graphic drawings and objects are represented as composite hypermedia nodes. Inference and critiquing are implemented through use of what are known as virtual structures [Halasz 1988], including virtual links and virtual nodes. These nodes and links are dynamic (computed) rather than static (constant). They are defined as expressions in the same language used for queries and are computed at display time. The implementation of different kinds of functions using a common set of mechanisms makes it easy to use them in combination, thus further augmenting the system's functionality.

PHIDIAS supports design by informing architects as they develop a solution's form. The idea is thus not to make the design process faster or cheaper but rather to improve the quality of the things designed. We believe that architects can create better buildings for their users if they have better information. This includes information about buildings of given types, user populations, historical and modern precedents, local site and climate conditions, the urban and natural context and its historical development, as well as local, state and federal regulations.