1. IntroductionThe physical internet refers to a hyper-connected logistics system that improves by an order of magnitude, the efficiency by which phys- ical objects are moved through the supply network (Pan et al., 2017; Montreuil, 2017). The two major parts of the physical internet are: first, a Fulfillment Warehouse (F-Warehouse) where online customer orders are converted into a physical delivery package; and second, a parcel delivery network which transfers the package from the F-Warehouse to the customer address. The physical internet is growing rapidly and replacing the large supply chain network which forms the backbone of the online retail economy. Both pure online and omnichannel retailers are designing and building facilities to stock thousands of different items and fulfill tens of thousands of daily customer orders in very short times. Some F-Warehouses are simply adapted from traditional warehouses and are similar in structure to the more classical mail order fulfillment facilities .