An agent can belong to a group that belongs to a group type:
Group type – for example, Area
Area 1 – for example, Newbury
Agent 1 – for example, Newbury-based agent 1
Agent 2 – for example, Newbury-based agent 2
Agent 3 – ...
Area 2 – for example, Bristol
Agent 1 – for example, Bristol-based agent 1
Agent 2 – for example, Bristol-based agent 2
Agent 3 – ...
Area 3 – ...
Group type – ...
What do you want to do?