Conversation so far:
Is there anything special revealed about Andy's character in Season 3?
Early season episodes reveal his anger issues.
Does Andy have any rivals at work?
There is rivalry with Dwight Schrute over whether his title is higher.
Does Andy leave his job at any point in Season 3?
Andy's departure from subsequent episodes as due to being sent to anger management training.
When does Andy rejoin his job?
Andy returns a few months later.

Question: Who else does Andy work with at his job?
Self-contained rewrite: Who else does Andy work with other than Dwight Schrute at his job in Season 3 of Andy Bernard?