Minimum viable tree

What makes a diagram a Tree of Influence.

A diagram is a Tree of Influence if it has all of these:

1. Nodes that represent elements of a problem space.
2. Directional arrows that represent influence between nodes. An undirected graph of sticky notes is not a Tree of Influence.
3. A construction process that starts with open contribution and moves toward refinement.
4. A legend that documents what the colors and arrows mean.

Valuable additions

Everything else is valuable but optional:

• Artifact / deliverable nodes. A tree with only root / problem, action / intervention and desired state / outcome nodes is complete.
• Typed relationships. A tree that uses only the default influences arrow is complete.
• Updates over time. A tree may live for one session or for years.