How much to put that doggy in the window?

In the reception room of animal shelter here, Rose Vicars and her son are struggling to hold a puppy they found abandoned at the side of a road.

"We think he's lost," Ms. Vicars says of the fluffy canine. "We have two dogs already, so there's no way we could keep him."

Today, however, Ms. Vicars' good Samaritan act of saving the pup from starvation or worse comes at a price - $25 to be exact. Earlier this month, the Humane Society of Southern Arizona became one of the first in the nation to start charging people for dropping off unwanted pets.

The fee - meant to discourage people from simply discarding their dogs or cats - is one of several steps that animal shelters are now taking to deal with a burgeoning problem of unwanted pets in many parts of the country. It's estimated that US shelters admit 8 million cats and dogs per year. In this Tucson shelter alone, 20,000 animals have been brought through the reception room in the past 12 months.

"We hope this adds a value to the pet in people's minds," says Susan Wilson, the shelter's executive director. "We want to people to stop seeing animals as disposable."

Judging from the quiet reception room, it may be working.

"I knew about the fee," Vicars says, rubbing the squirming pup. "But we couldn't just let him get hit by a car."

The problem of overcrowded shelters varies from region to region - shelters in New England and California sometimes don't have enough animals to meet adoption demands - but "the rest of the country is not that lucky," says Martha Armstrong, vice president for companion animals with the Humane Society of the United States.

These differences are reflected "in communities that have really progressive animal care and control programs in place, and those that don't," says Ms. Armstrong.

Such initiatives can range from incentives - lower licensing fees for sterilized animals, for instance - to breeding restrictions. Overall, more and more people are neutering or spaying animals. The result is that the number of pets euthanized at shelters has dropped from about 13 million in the 1970s to between three and four million today.

Regardless of steps to keep unwanted breeding down, the number of unwanted and euthanized animals "is still very large, and it's still an issue," says Andrew Rowan, chief of staff for the Humane Society of the United States.

The reasons people abandon their pets range from behavioral - aggressive dogs or spraying cats - to landlords who prohibit pets. In some areas, such as the South and Southwest, traditional attitudes towards animals have also hindered progress.

In those areas, some are more likely to see pets in a "utilitarian way," and are more likely to take them to shelters when they are deemed useless. "The animal is looked at as a companion. But it is also looked at as serving a function," she says. "Does the dog hunt? Does the dog bark and keep people away from our property? Is the cat going to be a mouser? It's an 'earn your keep' sort of thing."

As people dump unwanted litters or animals deemed a burden, shelters are looking beyond just charging fees to cope with the boarding costs of their full-capacity facilities. They are also taking aggressive steps to encourage animal adoption, including showcasing animals at shopping centers or community events.

They're making shelters more visitor-friendly, too. For example, In New York, a shelter run by the American Society for the Prevention of Cruelty to Animals strategically placed a free-roaming "urban cat habitat" next to the front windows to pique the interest of passers by. "We also have a get-acquainted room, where people can meet their [potential] pets," says Ruth Goldstein, a shelter spokeswoman. Tucson's shelter has followed the trend as well: It has a lawn where people can play with the cats and dogs.

But it's the shelter's fee policy that has garnered the most attention. It is now the third animal haven in Arizona to start charging people who drop off animals. Elsewhere, a sanctuary in San Diego and another in San Francisco have similar policies.

Not everyone favors the idea. Martha Armstrong says that people who have emotionally divorced themselves from an animal - to the point that they are willing to take it to a shelter - are not likely not take good care of the animal if forced to keep it.

But some say it's a misconception that all people drop off pets without reflection. "These are often long and complex decisions that people go through - not just a spur-of-the-moment thing reflecting that they don't value the animal," says Dr. Gary Patronek, director of the Tuft's Center for Animals and Public Policy in North Grafton, Mass.

Shelters can help people contemplating dumping pets, says Mr. Rowan. "The new message is 'Come to us if you're having trouble.' We want people to come to us early, before they make the decision to hand the animal in."

But on the ground, the task of dealing with a deluge of unwanted animals remains daunting.

"It's human shortsightedness that brings animals here," says Ms. Wilson at the Tucson shelter, her weary tone fringed with disgust. "We need to change the culture of this community, so animals aren't taken for granted."