But more than a century later, in 1978, its leadership had grown tired of the organization's serving dual roles as a killer and a savior of animals.
Backing out of its long-standing shelter contract with the city meant losing more than a fifth of its annual budget, but then-president Avanzino felt the group's agenda no longer fit with the city's mechanized handling of hapless animals. Thousands were still being killed by the city each year.
"For 101 years, the reputation of the SFSPCA was, 'That's the place where animals are killed,'" Avanzino said in a 2000 interview he gave to Maddie's Fund. "That was not the purpose of our organization. You can't be the animals' best friends and be their principal killer."
The city was forced to create a separate municipal shelter, known today as the Department of Animal Care and Control, which cites abusers, seizes dangerous dogs, and maintains its own adoption program. The SPCA then proceeded to vastly expand its spaying and neutering services, particularly for juvenile animals, as well as its medical facilities and treatment for animal behavior previously regarded as severe enough to warrant a trip to the death chamber, in which dozens of animals were killed at once. A technician withdrew oxygen from a decompression room until they died.
The SPCA led the way in taking animals waiting for adoption out into the community, and while some early skeptics feared mobilized adoptions would inspire impulse buying and high turnovers, many groups nationwide started to follow Avanzino's lead after seeing how well it worked here.
On its sweeping Mission property at 16th and Alabama streets, where the SPCA has been located for almost a century, the shelter did away with cell-style kennels, which encourage erratic behavior and reduce the chances that an animal will find a home. In 2004, the most recent year for which figures are available, the city found homes for 4,500 dogs and cats, with the SPCA handling three-fourths of those adoptions.
And guaranteeing homes for cats and dogs defined as adoptable, let alone those who are arguably treatable with the right commitment of energy and resources, was almost unheard of in the mid-'90s, when San Francisco made its promise. Under San Francisco's agreement with the SPCA, animals considered adoptable include cats and dogs eight weeks and older, those without "temperamental defects," and those not suffering from life-threatening diseases or injuries.
However, while a 100 percent adoption rate is probably not possible, Winograd and others worry that the bedrock of the nation's no-kill movement has failed to reach its full potential since Avanzino left, and they say the San Francisco SPCA could at least aspire to a save rate of more than 70 to 80 percent.
"I think the agency went through some times they weren't used to, not having a long-term leader that really understood the history of the organization and the goals of the organization," Carl Friedman, director of Animal Care and Control, said of the SPCA. "But that happens everywhere. I think it took a little bit of a toll on the organization."
Friedman worked at the SPCA for several of its most memorable years before moving to the city's municipal shelter in 1988, after the SPCA relinquished its role as the proverbial dogcatcher. He says that most euthanized animals in San Francisco are cats and dogs struck by automobiles or those suffering from parvovirus and distemper, both preventable with early vaccinations.
It's worth noting that the agreement between Friedman's office and the SPCA forbids each of them from speaking critically of the other, and many of the people we talked to balked at speaking on the record.
"People are afraid of getting sued, and they're afraid of what will happen," Winograd said. "There are people in San Francisco who need these agencies.