The Model and its Architecture explores the relation between knowledge and models in both scientific and architectural discourse. The significance of the model for Platonic philosophy and the contesting of this in the work of Deleuze forms the background for a consideration of the consequences of the debate in current architectural practice. At the heart of these responses is the problem of process, of design, cosmology and creative work within the layered relations of philosophy and architecture. The various conceptions of the model for architecture are examined in the writings of Vitruvius, Renaissance theorists, and philosophers of pre-modern Islam.