Allowing a student to sit in during class I'm a grad student who will be teaching a course for the first time over the summer, and I'm not sure what the convention is on allowing a student to "sit in" on the class (that is, attend class without being registered, not getting credits, etc). If a student asks before class for permission to do so, is it to my discretion on whether or not to allow it? I suppose it's always within the instructor's right to deny the request, but it seems like approving the request without the school's permission could be a mistake, since I am an employee of the university. The faculty handbook seems to only consider if the student audits the course, in which case they have to officially register as auditing the class, but nothing about unofficially sitting in. Am I extending past my right as instructor if I let a student sit in?

EDIT: This is at a private university in the US.
If you want to find out what exactly is within your legal power as an instructor and what is not, check your university regulations. They do vary from place to place. The general rule is that if there is no official policy in the handbook, the choice is yours, but you may also ask the chairman to be on the safe side (this is a good general strategy, by the way: while in doubt and seriously concerned about any legal stuff, just pass the issue up the administrative ladder). As to the rest, I usually allow people to sit in whenever they request it under two conditions

1) The classroom sitting capacity allows it

2) The student behaves in a non-disruptive way

So, unless you have a clear reason to say "No", I would say "Conditional yes" and tell the student any conditions you care about right away with the understanding that if any of them get violated, the sitting-in gets terminated.