Despite a plethora of knowledge, both behavioural and neural, of the mechanisms defining space around a singular body little is known about the neural mechanisms that encode space between bodies. Yet, the space between people creates and defines the social dynamics of our interactions with others. This review brings together evidence from social psychology, which considers individuals and their interactions as whole beings, with neuroscientific evidence of the factors involved in spatial coding to propose a framework by which we can investigate and interpret the neural substrates of 'social space'. A key feature of this framework is that space around the body is defined from a functional 'action-centred' perspective; the same underlying processes mediate interactions with both inanimate and animate objects, with links to emotive and motivational systems encoding the saliency of those interactions. The investigation of the neural mechanisms underlying interpersonal space is timely given the increasing density of our populations and can provide a richer interpretation of findings from neuroimaging studies of prosocial behaviour which may further insights into populations with social dysfunction.