Asynchronous item delivery utilizes a system including a first depot and a first mobile robot at a first site and a second depot and a second mobile robot at a second site. A centralized control system manages asynchronous delivery of items through the first depot and the second depot such that the first mobile robot can retrieve an item from the first depot and deliver the item to a transportation systems for transition to the second site, such that the second depot at the second site can, in an asynchronous fashion, receive the item and deliver the item to the second mobile robot for transportation to the ultimate destination at the second site. Two or more sites can be coordinated by the centralized control system for management of movement of items through a supply chain using asynchronous item delivery and movement through each respective site to an ultimate destination.