This thesis confronts and analyses the relationship between internal (compositional) spatial thinking and aspects of external (performance) space, with the intention of revealing new musical possibilities. Eight original electroacoustic compositions are presented in the portfolio. These are Anima Machina, Bosonica, Cipher, Papyrus, Pavakoothu, Spindlesong, Topographia and The Spindlesongs Installation. The works exhibit a variety of spatial characteristics, not only through the spatial implications of the sound material used, but also in their presentation formats. The portfolio comprises four stereo works, one 5.1 work, two 8-channel works and a work for solo instrument (clarinet) and electronics. All but one of the compositions are acousmatic, and the mixed work is greatly informed by the acousmatic tradition. The main concern spanning the portfolio is the creation of spatial aspects on a number of levels, from source material through processing, layering and spatialisation to dissemination in performance. The commentary presents supplementary information on each work, with a view to providing the reader with an insight into the evolution of my compositional vocabulary. Those aspects considered spatially most significant are highlighted, with reference to the current musicological terminology of space-form (Smalley 2007) and other contextual writings in the field. The research findings are assembled according to the nature of spatial presentation: stereo, multichannel, installation, and instrumental performance.