The number of dogs and cats put to death in U.S. shelters is about one-fifth of what it was four decades ago.

“They were euthanizing about 15 million pets back in 1970,” said Betsy McFarland, vice president of companion animals at the Humane Society of the United States. “We’re now down to about 3 million every year. Of course, that’s 3 million too many. But that is tremendous progress that’s been made over the last four decades.”

During that same time period, the number of dogs and cats in the U.S. increased from 64 million to more than 160 million, according to Humane Society estimates. McFarland attributes the decline in euthanasia rates to spay/neuter campaigns targeted to underserved communities, better coordination among animal welfare organizations and changing social attitudes toward pets.

“I mean pets are really considered part of the family,” McFarland said. “And that has been a shift over the many decades where maybe pets were a little more utilitarian.”

Although the number of pets entering shelters has decreased nationwide, euthanasia rates at these shelters average close to 50 percent. But the Humane Society and other groups say their goal is to bring the number to zero, and they’re finding creative ways to head in that direction.

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In the Atlanta area, the non-profit LifeLine Animal Project has helped two shelters lower their euthanasia rates from historic highs of 85 percent to less than 20 percent. LifeLine, which now manages shelters for Georgia’s DeKalb and Fulton Counties, brings its pets to adoption drives at shopping malls and other areas with large crowds. LifeLine also keeps many animals from entering shelters by offering “surrender counseling” to owners who are considering giving up their pets.

“What we found was that so many of the calls from the people who wanted to surrender their pets, they didn’t actually want to surrender their pets,” said Debbie Setzer, Lifeline’s community outreach director. “They may have had some financial hardship where they couldn’t afford dog food. They may have had a fence complaint where the dog was getting out.”

Pet owner Adrian Robinson, who’s already caring for a foster child and two adopted kids, says she felt overwhelmed when a highly energetic puppy joined her household.

“Keno doesn’t know his own strength,” Robinson said. “He was running around, jumping on the kids.”

LifeLine arranged free neutering, vaccinations and a training crate for Keno that helped calm him down and made it possible for Robinson to keep him. The mother and pet owner says she’s grateful to LifeLine’s staff for their assistance and advice.

“I love them,” Robinson said. “They did something for me that I couldn’t do for myself.”

Lifeline has helped other owners by repairing fences and helping them obtain donated pet food.

“Anything that we can do to keep that animal from coming into the shelter, we’ll try to do,” said LifeLine CEO Rebecca Guinn.

Before helping to create LifeLine, Guinn worked as a lawyer specializing in white-collar crime. While assisting a neglected dog in her neighborhood, she learned about the high euthanasia rates at her local shelter. Reducing those rates became her new passion (and full time job).

“There are more pets in American households than there are children. So, they’re a part of our lives,” Guinn said. “The idea that we use taxpayer dollars to round them up and then end their lives, to me, is not the right way to do it. And we’re working on a model where a shelter is truly a shelter -- where the pets come in here, receive the care that they need and then can be re-homed -- and where the community at large becomes a better community for pets to live in.”

Fox News' Chip Bell contributed to this report.