It's 9:20 on a cold Wednesday morning in Cleveland Park, an affluent neighborhood in Northwest Washington, D.C. Three homeless men are lined up outside the public library at Connecticut Avenue and Macomb Street. Waiting for admission, they have been huddling close to the door to avoid the biting wind. As a custodian unlocks the door, they hurry inside, one rushing to the computer, another to a desk in the back corner.

Because shelters empty their beds by 7 a.m. and don't reopen their doors until 7 p.m., libraries become de facto housing for the remaining 12 hours in the day for many homeless men and women in D.C. Consequently, library employees face the tricky balance of serving homeless patrons looking to use the library resources and monitoring others who are just looking for a warm, clean place to rest.

Some homeless library patrons use the free computers to look for jobs or to e-mail friends and family. Rick Hohensee spends two or three hours at the Cleveland Park Library nearly every day, arriving by bus or on foot. He uses the computers for research and political activism, but he also enjoys conversing with library staff and volunteers.

Other homeless patrons come to the library for weather protection, solitude or safety, or just to pass the time.

"We do 'house' homeless people, but not formally," said Monica Lewis, director of communications and intergovernmental relations for the D.C. Public Library system.

"While the library welcomes all, its purpose is to help users increase knowledge, find entertainment, access technology, communicate using e-mail, etcetera," Lewis explained. "It is difficult for libraries when some use [them] to sleep and to bathe." According to Ginnie Cooper, the newly appointed chief librarian for the D.C. Public Library system, librarians are instructed to ask sleeping patrons to sit up when they rest their heads on the tables or equipment. If they resist, the librarians at the central library are directed to call the security office.

Capt. Frederick Williams, head of the library's public safety office, said that his force has good rapport with most homeless people. Security officers greet and chat with homeless patrons and remind them to take their medication.

Sometimes, however, homeless people are found sleeping in stairwells, nooks and crannies. To help discourage improper sleeping, closed-circuit cameras scan the halls of the downtown Martin Luther King Memorial Library (MLKML).

The downtown library has a greater number of "homeless visitations" than do the branch libraries. Its proximity to shelters, soup kitchens and Catholic Community Services means that D.C.'s homeless residents often sleep under the library's awning and in its alley.

In September 2005, a homeless person resting outside the library assaulted and injured a library security officer. On several occasions, patrons have been shocked to find homeless people bathing in the nude in the restrooms. Some restroom doors are now kept open permanently, according to the library system's Monica Lewis.

Improper bathing and grooming also are issues at the West End Library in Georgetown. In addition, some homeless people there formerly went to corners of the building, occupied several seats and ate, which was prohibited. "We had to reorganize the reading area to make hiding more difficult," according to one West End manager.

Patrons who hide pose a challenge for branch librarians, especially when they prepare to close for the night. For example, two people hiding in the Cleveland Park branch were discovered only after the library closed when a motion detector caught them.

Recently, a homeless man named Bayo, who was resting in the carpeted basement corridor of MLKML, said he comes to that library about three times a week. Sometimes he just uses the restroom, and other times he reads or sleeps. Bayo said he has no problems with the staff, although someone occasionally wakes him if he sleeps on the floor.

Vincent Adkins, who also is homeless, moved to D.C. from Texas five months ago and now visits the library when he is out of work. Like Bayo, Adkins likes the comfort of the library, which is cool in the summer and warm in the winter.

A library helps ground Adkins and others who are recent arrivals in the area. A sense of community is important to D.C.'s homeless population, and libraries are one place they can make friends, keep up with the local news, study for a class and experience a sense of belonging, one advocate for the homeless noted.

Visiting the library is a positive activity, especially for those trying to recover from an addiction or deal with mental illness, the advocate added. Even on the happy occasions when people leave shelters for their own apartments, the library serves an important role in combating loneliness.

Despite the homeless population's dependence on libraries, however, the libraries have no control over the number of homeless patrons they serve. And there certainly is no "homeless services" allocation in their budgets, according to library officials.

In addition to citing increased security and maintenance costs associated with homeless visitors, many librarians argue that they are professionals in their discipline - library science - and not trained social workers.

"I feel that using the library as a shelter is not fair to other library users or homeless people. We have complaints and issues many days due to the number of homeless that come in and stay in the library," said one branch librarian, who asked that her name not be used. "I am happy to help with informational needs, but I am not a social worker. Most of the homeless people that come in everyday have social, safety and security needs that we just can't meet."

Jill Bogard, president of the Friends of the Cleveland Park Library, also has strong feelings about homeless patrons in her library. "Since the library is a public space, homeless people are legally entitled to be there. However, the mission of the library is not to serve as a temporary shelter for homeless people,'' Bogard said. ``The folks I've seen in the library are usually sleeping - they are clearly not there to read the paper or do research."

Still, the D.C. Public Library's Lewis remains optimistic. "Libraries are the nation's universities. We just want to make visiting the library a fun experience for all users," she said.

Chief librarian Cooper reiterated Lewis' sentiment and said that libraries, by design, admit anyone and everyone. "Libraries,'' she said, ``are the most democratic organizations in the country."

Mandy McNally contributed to this story.