Bricks, Masonry, Asphalt and Concrete - Rebar needed?

In what instances is rebar needed? I am having a pool installed and I was told that the concrete around the parimeter (3-4 feet out) would not need to be rebar re-inforced.
Does that sound right? Are there common rules of thumb?

I've poured concrete around many different pools for many different pool builders/companies, and none of them have ever had rebar. Some use wire mesh in the concrete, and some prefer fiber.

Pecos

So..is anything "required" ? Or,can they just pour concrete on dirt?

You wouldn't want to pour on "dirt". Generally speaking you would want several inches of compacted fill stone or sand as a base. They will have to backfill the pool overdig with it anyway, so I'm sure they'll put it under the concrete too.
One thing that IS required, at least around here, is a grounding wire attached to all the metal fixtures such as ladders, diving boards, and to the pool pumps, etc. to prevent electrocution.
Any reinforcement in the concrete should be included in the pool company's contract. If you want it and it's not in there already, expect to pay extra for it. If it's not in there, don't freak out. There's a lot of un-reinforced concrete out there that lasts indefinitely. There's also reinforced concrete that doesn't last more than a few years. It's all about proper base prep, quality of concrete, and competence in finishing. Good luck.

Pecos