Choose your recruiter like you would an employee, check to see:

Make yourself available when your recruiter calls. Tell them how many other agencies you are using. If it's too many, no one will work on your opening. Limit the amount of recruiters you use, i.e. 2. Have a relationship with your recruiter, so that he/she can best help you. Do not deal with someone who throws paper around.

Tell the recruiter how you want to work, i.e. fax resumes and then call or call and then fax resumes. Respond promptly if interested or not.

Make sure recruiter has spoken with candidate concerning your position.

Understand that the recruiter you use is your PR arm. How are they selling your company to the prospective candidates? Can they intelligently discuss your position? Be extremely timely with feedback when they call. Tell them what the next step is and let them set it up.

Have the recruiters obtain references. Discuss the offer with the recruiter first, so that they can make the presentation. The recruiter should know at this point, what it takes to close the deal.

Put the offer in writing. Fax copy to recruiter. Remember, the recruiter is there to help you fill that important vacancy that you need filled yesterday, so work with them.