Conventionally how states ‘infrastructured’ was based around the monocentrism of the positive state. The progressive liberalisation of infrastructure over the past three decades has given rise to polycentric national infrastructure systems (NIS). This polycentric NIS exhibits a higher degree of structural, spatial and operational complexity with the state being one player though it still plays a prominent role not just through its own activities but also in seeking to steer the system to meet its territorial objectives. This is done through the formal interaction between hard and soft infrastructure (with the later characterised by themes of sustainability, consistency and criticality) components of the NIS. These themes are explored through an analysis of the UK’s National Infrastructure Plan where – it is argued – the formation of the UK NIS is characterised by a strategy of sustainable polycentrism though this strategy has yet to deliver the investment anticipated.