This talk examines how illicit flows that cross borderlands shape security from the local to the global level. It introduces the concept of Global Illicit Supply Chain Networks to explain how trafficking hubs—places where several illicit flows intersect, often near borders—connect regions of conflict and instability with wider global systems. These hubs are not peripheral; they are crucial nodes where local arrangements, often between state and non-state actors, sustain both order and disorder. The analysis draws on multi-sited fieldwork across the Andean region, Southeast Asia, Iraq, and the Horn of Africa, combined with geospatial and network analysis. This mixed-methods approach captures both the lived realities of those experiencing insecurity and the structural patterns that link borderlands to global dynamics. By tracing how short-term, pragmatic alliances and overlapping illicit and licit economies reinforce each other, the talk highlights how local interactions can have far-reaching security implications. Rather than treating borderlands as marginal, it argues for recognising them as integral to understanding global security.