[Jeff Higgins]

If it is part of the compensation package agreed to by both parties when you accepted the job offer, there should be no question that it is your right to take it when you want. Any limitations on that right should have been spelled out in the offer. If they weren't, the implication is that there are no restrictions. Advance notice is a profesional courtesy and I believe an obligation.

One of the oldest employment tricks in the book is to offer attractive benefits packages and then not let employees exercise them. Vacation is the classic. "Use it or lose it" schemes abound, with employers having some time period in which you must use vacation or it goes off the books. Then they never approve any, so you lose it. Or "comp time" in lieu of overtime. What seems to be lost on many is that if you are busy enough to be working a lot of overtime, it's not likely any comp time will be granted. It's supposed to be when things "slow down", but such companies will then usually lay people off and keep those still employed working overtime anyway.