"With animal communicators, it's dicey," says Joe Nickell, a paranormal investigator and senior research fellow for Skeptical Inquirer magazine, which investigates psychic claims. "Let's say there's basically two kinds of pet communicators. There are those who really believe they can do this. Then there are those who are aware they can't, but they are pretending."

In his writings on the subject, Nickell says pet psychics employ the same "cold reading" techniques that fortunetellers use to gather information from a source "while giving the impression it is obtained mystically." These include stating obvious facts, asking questions and making safe or vague statements.

By comparison, animal behaviorists say, communication with animals is accomplished through observation and empathy, not telepathy or psychic abilities.

They observe behaviors and signals, then interpret that information based on science. Understanding and recognizing body language and then rewarding for desired behaviors are key to communicating with animals.

"It's through a mountain of science-based study, not from a gut reaction or personal perception," says Michael Shikashio, president of the International Association of Animal Behavior Consultants. "If someone claims to whisper or have psychic connections with animals, ask where they received their formal education and if their methodology is based in science."

Many conventional veterinarians shy away from using animal communication (at least telepathically). Consulted for this article, the Maryland Veterinary Medical Association declined to comment because no one in the organization was knowledgeable enough about the subject.

Dr. John Slaughter, a veterinarian with Camden-Inner Harbor Veterinary Services, says he finds pet communication amusing. He doesn't have back-and-forth conversations with animals, he says, but he can glean information from behavior and by talking to pet owners. Some of his clients have used animal communicators and felt their money was well spent, he says.

"Will it be something that I, as a veterinarian, would put my license on the line for? No. But it could be quite entertaining and possibly informative," Slaughter says. "I don't think the jury is in, whether an animal can communicate that way. I think it's becoming more popular because people are saying 'Is this bogus or is this real?' "

Hampstead animal communicator Diane Carlson says she sometimes tries to prove her legitimacy to new clients by asking animals to show or tell her something only their owners would know.

"Ninety-eight percent of the time, it proved to be right," Carlson says. And most of the time, Carlson says, she is right in discovering what might be bothering the animal. Carlson says she can figure out why an animal is sick or unhappy by sharing mental images.

Recently, Carlson says she helped a horse win a blue ribbon by adjusting the animal's diet.

Her recommendation?

The horse likes to "eat a lot of apples," Carlson says.

When people doubt Diener, she says her purpose isn't to provide proof. Her purpose is to help the animal, and Diener says her clients find out throughout the session that she's usually right.

Dr. Christina Chambreau, a Baltimore-based homeopathic veterinarian, embraces animal communication and says pet owners should look for another veterinarian if their veterinarian won't consider it.

While Chambreau can observe symptoms and behaviors, sometimes an animal communicator can pinpoint an underlying problem that might not be apparent, she says. Chambreau often consults with pet owners, veterinarians, behaviorists and animal communicators, as well as assessing symptoms to determine what might be bothering an animal.

"I recommend everybody learn to do it themselves and work with someone who has the skills in it and the expertise. You need to know what your animal is saying to you," says Chambreau. "Working with animal communicators is a rapidly growing area, as people wish to be more in touch with their animals."

Jackson Galaxy, a cat behaviorist and host of Animal Planet's "My Cat from Hell," believes many people have empathetic connections with animals, but pet owners should be wary of any quick fix.

"There is no magic bullet. You are responsible for your relationship with your pet," says Galaxy. "I don't want to short-circuit the process. There's a process involved. I just think you need to pay more attention to who these people are before offering to pay for their services."