Niche publications serving specific demographics, like gays, seniors or Koreans, can make a lot of sense, whether they are online or in print. But not every niche is the same.

Longtime YP executive Dick Larkin, the “Small Business Commando,” lays out some rules of the road for niche advertising in the latest edition of his newsletter.

“Your customers want respect, acceptance, and integrity,” says Larkin. “Advertising has to ring true for it to be effective.”

In selling to niche audiences, Larkin advises publishers to brutally assess their own strengths. The only publications that should get the business are those that better serve niche needs than competitors. A tougher question: Would they refer their own friends to a niche business?