Two organizations can work together without sharing a manager if each knows what the other will send, accept, and do next. A protocol defines the sequence and meaning of an exchange; an interface defines the boundary through which that exchange happens.
On the Internet, consistent specifications let independently implemented systems communicate. Between organizations, an agreed format also needs someone responsible for receiving, interpreting, and acting on the information.
Agree at the boundary
Several support organizations could adopt a common referral form and an acknowledgement procedure. Each could keep its own internal workflow while agreeing what information a referral contains, who receives it, and how the sender learns whether it was accepted.
The arrangement reduces repeated negotiation, but an interface can hide important context. A checkbox may fail to capture urgency, and a referral marked “sent” may still have no person responsible for acting on it. Exceptions need a route across the boundary too.
Protocols also distribute power. Whoever controls the format can make some kinds of information easy to express and others nearly invisible. The aim is enough common structure for reliable cooperation without demanding that every participant operate in exactly the same way. A good boundary preserves independence while making dependencies understandable.