How much advanced notice must an employer give that they want you to work overtime?? I as because the other day 45 minutes before we were to clock off for the day they announced there was 2 hours of mandatory OT...can they do that??

Yes, they can tell you as you are heading to clock out that you need to keep working or even snag you after your clock out and are heading for your car.

It is not convenient and, for some employees, may pose some major problems (child care comes to mind), but there is no requirement for advance notice of any sort.

I dont see how any employer can feel that is the proper way to conduct business...much less a proper way to keep employees...if it was the employer that had this done to them and had childrens buses to meet and such that they would not appreciate it either. I think the worst thing about it is the fact that if you even try to explain your situation..that they knew before you started...they just dont care and will take "corrective" action against you if you do not stay. I guess I just dont understand how they can feel justified in treating employees that way...but like they have said they can just call a temp service and have your position filled in a days time

An employer does not always know until the last minute whether overtime will be required. They can't give you advance notice when they don't know themselves.

Employers are no happier about requiring overtime (which they need to pay for) than you are about working it. They are responsible for running the business, not for your busses or child care.