This paper outlines a way toward conceptual and historical clarity around the question of territory. The aim is not to define territory, in the sense of a single meaning; but rather to indicate the issues at stake in grasping how it has been understood in different historical and geographical contexts. It does so first by critically interrogating work on territoriality, suggesting that neither the biological nor the social uses of this term are particularly profitable ways to approach the historically more specific category of 'territory'. Instead, ideas of 'land' and 'terrain' are examined, suggesting that these political-economic and political-strategic relations are essential to understanding 'territory', yet ultimately insufficient. Territory needs to be understood in terms of its relation to space, itself a calculative category that is dependent on the existence of a range of techniques. Ultimately this requires rethinking unproblematic definitions of territory as a 'bounded space' or the state as a 'bordered power container', because both presuppose the two things that should be most interrogated, space and boundaries. Rather than boundaries being the distinction between place and space, or land or terrain and territory, boundaries are a second-order problem founded upon a particular sense of calculation and concomitant grasp of space. Territory then can be understood as a political technology: it comprises techniques for measuring land and controlling terrain, and measure and control - the technical and the legal - must be thought alongside the economic and strategic.