Other differences are clear in the approach to the work. For the interior designer there is no equivalent of a clear site; the least limiting of interior space with which the designer must contend is more conditioned than almost all sites with which the architect is presented. Consequently there is a different consciousness required of the interior designer in the approach to his or her work. It is provoked by this condition of fitting, of always working with and within existing structures. Because of this, a structured understanding of the host building is an essential preliminary to the consideration of any intervention. The understanding needs to be a common language derived from the actuality of the built form, a language which will allow a mental deconstruction, informing the physical alterations. It requires of the designer a thoughtful stripping back of the host building. An understanding must be reached which is material, spatial and cultural.