[CaptainCrunch]

Having worked for an agency that does both placement and headhunting, I can tell you that some are very good, and some can be really dangerous.

The good ones do whats called skills marketing, in that they bring you in, test you, make sure that they understand what you want and how much you want to make, and then proactively market you to their client base if they don't have a active roll for you.

The bad ones will jam you into a roll and hope that it works out and you don't quit in the first three months so the client doesn't invoke his warranty clause.

But its more up to you to be thorough, its unlikely that they're going to let you know who they're recruiting for until your well into the process so that you don't go around behind their back, they're also their to negotiate for their client, and not you, so be suspicious of any office that comes to you from the head hunter or placement agency.