[Trogdor]

A friend of mine is an actuary. She did not need a graduate degree. They have their own tiered system. It's a series of tests that you take over the course of your career that work you forwards Fellowship. Once you are a Fellow that's more or less then actuarial equivilent of a PhD.

That said, graduate degrees are a fair bit of money, and a big time investment - especially if you're working full time. If you're not sure what exactly you want to go to school for, I would highly recommend you figure it out first before you make that commitment.