"I signed up with an agency that said it was looking for people who wanted to get into "executive" jobs at good salaries. . . . I signed up, eventually paid $2,700 and never got a job, not even a nibble."

This paragraph comes from a reader who fell for this advertisement: "Our business is placement. . . . We avoid false-hope promises in favor of reality."

The "reality" is all to clear - the reader was taken. The more an agency promises to get you a high-sounding job, the more you should run, not walk, in the other direction.

"The legitimate placement agencies," says Richard Hill, executive director of the National Association of Personnel Consultants, "never charge the applicant a fee until a job has been found and accepted." Sometimes, Hill says, "no fee is charged to the applicant - the employer pays."

As a rule, in the high-paying jobs, the employer pays the fee. In true "executive search" organizations, says John Schleuter, director of the Association of Executive Recruiters, "the employer always pays - always."

So, rule No. 1: If you are obliged to pay more than $5 or so registration fee without an absolute, guaranteed job at the end of the process - you will probably lose your money. No job - no money. That's the rule.

If the reader who got soaked $2,700 for "nothing" had only read the contract's fine print, he would have noticed a disclaimer that says, "No placement is guaranteed." The advertising all but promises placement - but not quite.

So, rule No. 2: Always read any employment search of placement contract several times and ask a lot of questions if you don't understand the jargon. Also, most states and some cities or counties have licensing laws for placement agencies. Ask about the license along with the contract. If the license does not say the agency is in the "placement" business, watch out.

Be sure you know who pays what fee under what circumstances. When an emlloyer pays the fee in some instances, you may have to pay a portion of the amount if you leave the employer before a specified deadline (from three to six months).

Know your rights and obligations. If you have a problem with an agency, get in touch with your state or local enforcement office (usually Department of Labor, but sometimes Consumer Affairs Department).

Finally, rule No. 3: Know the different types of employment or job search agencies. There are four:

Placement. These are usually referred to as employment agencies. Except in Vermont, Mississippu and Alabama, licensing is enforced. You never pay a fee except, perhaps, a small registration fee, until you get a job. Often, the employer pays.

Some employment agencies have branched out into "search" organizations (recruit for employers) and temporary employment. Applicants are not charged fees in these circumstances.

Executive recruiting or search. Sometimes called "head hunters," these companies are paid by employers to find special employees usually in management or in the professions. Sometimes they work on retainer, sometimes the employer pays the fee when someone is hired. But, applicants never pay a fee. Job seekers' resumes and (if possible) interviews are welcomed, but no "placement" is promised.

Executive counseling. These organizations do not officially promise to get you a job (read the contract). Some help you prepare youself and mail out your resumes. Some job seekers swear by them. Some swear at them. "You take your chances."

Temporaries. Your work for the agency, which "rents" you out to employers. They're great for housewives, students and others who want to work part-time.