Orchestrate Collaboration
It is ideal of people initiate collaboration on their own. Indeed, a core assumption of the Agile community is that collaboration will occur spontaneously if managers merely get out of the way.
It does not always happen though. In fact, while it often happens within a team, collaboration across teams is less likely to occur. Product developers are often a little introverted, as a population, and they tend to want to isolate themselves. That is why among teams that build microservices, there is a strong tendency to want to build a “wall” by defining an API and then insisting that if anyone uses the API incorrectly, it is the API user’s fault, even if the overall product is broken.
Good leaders set the bar, by demonstrating cross-team collaboration. They do that by asking questions, and bringing people together. They make sure that relationships across teams get built. They set the expectation that if someone has an obstacle that another team might be able to help solve, they reach out to that other team.
Good leaders also ask things like “How are you and that other team coordinating your work? How are you managing your dependencies so that neither of you has to wait for the other? How are you ensuring that the other team can use your stuff well and will not misinterpret it? How are you making sure that the work between teams is integrated frequently? And where are you documenting decisions that you and the other teams make, so that other people can see it? And are you making sure that people who might be affected by those decisions are told?”
Leaders need to make sure that these things happen. It is important that a leader not become the key person who is needed to make decisions or to make collaboration happen. Rather, a leader should be training others to do those things, even if the leader reserves the right to make final decisions. People need to know that they are empowered and expected to make decisions on their own, and that as long as they are transparent about the risks, they are supported.