Is there any capacity using the API to retrieve a list of departments, sub-departments and positions? I can't see anything in the documentation.
The only way currently to do this would be to pull a list of all your people with their departments and compile the list through this.
We're going to be re-working our API in the future though and this is something that we'll be looking into in the future.
Hope this helps,
If that's the only option, I'll look at going down that route.