Illegal goods are trafficked through couriers with whom legal contracts cannot be enforced. We model the problem of these couriers absconding and focus on a finite horizon problem in which trade cannot be sustained through reputational effects. Nonetheless, trade remains possible if there are sufficient gains. Optimal schemes have one courier making numerous, but a finite number of, return trips, being entrusted with bundles of increasing value, and keeping the last. Our model is robust to (i) punishment, (ii) bonding and (iii) a competitive market for couriers. We discuss implications for interdiction and how the model fits some ancient trade as well. I.

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