Throughout the last decades, research has generated a substantial body of theory about Spatial Presence experiences. This chapter reviews some of the most important existing theoretical explications. First, building on notions offered in literature, the core of the construct will be explicated: what exactly is meant by the term "Spatial Presence"? Second, theoretical views on the "feeling of being there" provided by different Presence researchers are introduced. Important aspects and determinants of Spatial Presence have been highlighted in the past, such as attentional processes and embodied cognition. However, coherent theoretical frameworks are rare and more empirical research seems necessary to advance the theoretical understanding of Spatial Presence. The chapter concludes with an overview about recent controversies and future trends in Spatial Presence research.