Indeed, the SFPL’s mission goes beyond connecting people with books and research material. In 2009, it was the first library in the country to hire a full-time social worker. Today, its staff of seven Health and Safety Advocates, or HaSAs — all of whom were once homeless — monitor the library’s six floors and bathrooms, offering resources on shelters, food kitchens, and clinics across the city to homeless patrons.

The idea for the HaSA program came about around 2000, just four years after the completion of the new $126.5 million main branch. At the time, homeless patrons in the library had become much more visible. “We had this beautiful new library, and we were hearing from patrons that they were uncomfortable coming there,” remembers the former chief of the main, Karen Strauss. “We set out to create a bridge between the people who come to the library as a safe and welcoming place and the resources that they might not know are available.”

To build that bridge, the SFPL partnered with the San Francisco Department of Public Health and, in 2009, hired Leah Esguerra, the country’s first in-house library social worker. A licensed marriage therapist counselor by training, Esguerra says her job has evolved significantly over the last seven years. “When I got here, I asked my former supervisor [at the city Department of Public Health], what am I going to do?” Esguerra said. “She told me, ‘Start building relationships.’ That was the best advice I ever got.”

Esguerra has done just that, creating a new model of outreach based on empathy and personal relationships. Her job includes not just counseling the homeless, but consulting with staff about how to interact with their neediest patrons. The library has also partnered with the non-profit Lava Mae, which operates a bus with showers outside the library two days a week. (Since its program was introduced in 2009, several public libraries across the country — including in D.C. and Denver — have followed the SFPL’s lead, hiring their own in-house social workers.)

But the most important piece of her work — and the one she is proudest of — are the library’s Health and Safety Associates, former homeless people employed as outreach workers. “The HaSAs are the backbone,” Esguerra said. “As a social worker, I can tell you to go to MSC-South [shelter]. But the HaSAs can take it to the next level. They can say, ‘This was my experience at MSC-South.”

Jerry Munoz is one of the Main’s six HaSAs (rhymes with “casa”). Stocky and clad in baggy blue jeans and a black T-shirt, Munoz zigzags a well-worn path, monitoring activity on computer terminals, scouting the desks along the margins of the stacks. In a single day, Munoz and the other on-duty HaSAs make three or four rounds through each of the Main’s six levels. He looks for telltale signs, like large bags stowed under tables or bottles of prescription medication scattered across desktops. Once he reaches the first floor he checks the men’s bathroom, to ensure that no one is using the sinks as showers or getting high in a stall.

Jerry Munoz holds his thick binder stuffed with forms and information about the various San Francisco social services library patrons can potentially take advantage of. (Jeff Enlow/Timeline)

As a former homeless patron of the main library himself, Munoz knows the choice spots—places where one can hide out from staff undetected. A native of southern California, he was a supervisor at a J.C. Penney’s distribution center. Then, on Father’s Day in 2010, his 25-year-old son, Joshua, who was getting ready to enter a graduate school program at U.C. Berkeley, died suddenly of a brain aneurysm. “Basically, I just flipped,” he said, describing his rapid descent into alcoholism and homelessness.

As we walk the first floor, Munoz sees an elderly man in a dirt-stained Golden State Warriors jacket sitting in a chair, his head slumped awkwardly forward. Munoz knocks on the wall just above him. The man’s eyes snap open. “Sir, you can’t sleep in the library,” Munoz says, polite but firm. Munoz asks if he can help with anything — a place to get a meal, somewhere to sleep. The man shakes his head, staring ahead blankly. Munoz leaves him in peace. In this job, he says, it’s important to know when to push and when to back off.