
What it is
A Team Alliance is a ceremony as much as a method. It's the explicit contract about how we work together: communication norms, decision rights, feedback style, and how we recover when things go wrong. It also covers how we want to work with other teams, not only how we want to be with each other.
Sometimes we take for granted that everyone thinks the same. This is how you find out they don't, and align on expectations before the politics starts.
I facilitate it as a workshop: how we want to interact, communicate, and handle mistakes. The output is a team vision you can actually use.
Defining how we want to be as a team
Team members get 5 minutes to add post-its on team values, goals, and expectations. Then we discuss and vote on the most important ones. That shared picture is how the team wants to operate.

Communicating as a team
Then we define how we want to communicate: styles, channels, how often. I asked them: When we are in conflict, what do we want to do? And what do we not want to do?

To finish the activity and to make them forget about their rational part, I asked them to look for a picture that they related to all the things that we said.

Conclusion
It isn't a poster. It's a ceremony we return to. When something goes wrong, I bring the alliance back into the room: how we want to work together, and how we want to work with other teams. That's when it earns its keep.
That same conversation has opened later workshops: motivation, a specific topic, a change we needed to name.

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