The question of how horizontal collaboration can be achieved in the Physical Internet is so far unanswered. The advantages of collaboration do not seem to outweigh the concerns about trust and data security, which is why only a few companies focus on joint logistics activities. Instead, logistics processes are increasingly in-sourced. However, even such internalization raises questions regarding free market structures. This paper provides an overview of horizontal collaboration in logistics and to what extent in-sourcing of logistics processes might be the easier solution to implement the Physical Internet.
