A list is a set of choices (Low, Medium, High). A tree has branches (UK → Midlands → Birmingham → Office 3).

Edit values
Lists and trees are edited as an outline: type a value, press Enter for the next, indent to make a branch. Use the arrow keys to move about.
Start from a template
Start from a template offers ready-made lists: severity, likelihood, impact, RAG, effectiveness, root causes, priorities, progress, yes/no, departments, incident types, months, quarters, days, countries and regions, and more. Choose Replace them or Add after them.
Tags
Tag values to say what kind of thing they are, for example Region or Office. Tags drive the role generator in Roles: "make a manager role for every Office".
Values are never deleted
Once published, a value is retired, not deleted, so old items keep their meaning.
Each Topic has its own
Trees aren't shared between fields or Topics. To reuse one, copy it.