A veritable tent city squats in Harvard Yard where lawn chairs should soon be unfolded for commencement. Protest messages painted on sheets flutter from ropes tied between trees, and bongo drums resound in time to political chants: "What's disgusting? Union busting. What's outrageous? Harvard's wages."

For more than two weeks, a group of students and young alumni have occupied the first floor of an 18th-century brick building that houses freshman dormitory rooms and administration offices -- including the quarters of President Neil Rudenstine -- at the nation's oldest and wealthiest university.

In a move that caught officials by surprise, 46 demonstrators carrying sleeping bags, computers and a week's supply of food strode into Massachusetts Hall on April 18, refusing to budge until Harvard agreed to give its lowest-paid workers a "living wage."

Thirty-five remained as of Thursday -- pale, tousled and smelly, but buoyed by outside support and a determination to continue Harvard's longest sit-in.

"We're staying until this issue is addressed in a substantive way," said Aaron Bartley, 25, a third-year law student from Buffalo, as he leaned out a window to speak to visitors restricted by police to a three-foot buffer zone. "We feel like we have a responsibility to make progress on ending poverty at Harvard."

Less than two months ago, Brown University students rallied against the school newspaper's publication of an advertisement opposing slavery reparations. And most recently, Pennsylvania State University students camped out for more than a week in the student center to protest death threats against the head of a black student caucus and to call on the administration address racial tension on campus.

Harvard's predicament appears particularly awkward, with the sit-in coming not long after the university -- whose endowment exceeds $19 billion -- announced a highly successful conclusion to its $2 billion capital campaign and appointed former treasury secretary Lawrence H. Summers to succeed Rudenstine in July.

"Reading period," typically a time of preparation for final exams rather than open rebellion, also begins today.

The occupation is part of a nearly three-year campaign by members of Harvard's Progressive Student Labor Movement to force the university to pay all custodians, dining hall staff and security guards a minimum of $10.25 per hour. That is the same amount adopted two years ago by the Cambridge City Council, which figured that workers need that much to afford the high cost of living in Cambridge. The council lobbied Harvard, the city's largest employer, to follow suit.

The federal minimum wage is $5.15 an hour.

According to protesters, as many as 2,000 Harvard employees -- including casual workers and subcontractors -- are earning less than $10.25 an hour at any given time, and many lack basic benefits. They say it would cost Harvard $10 million a year to implement a living wage policy -- less than one-half of 1 percent of the annual interest on Harvard's endowment. By comparison, Massachusetts Institute of Technology custodians receive at least $12.03 an hour.

Harvard officials contend that only 403 of the school's 13,500 "regular" workers earn less than $10.25 an hour and that no full-time employee earns less than that amount when the cost of benefits is included. About 500 subcontract employees earn less than $10 an hour, they said.

Last year, a committee studying the pay issue rejected a wage standard. They advocated collective bargaining and suggested expanding health benefits and providing improved job skills and literacy programs for university workers.

"We believe in the same principles as the students in terms of fair, dignified treatment of workers," said Harvard spokesman Joe Wrinn. "Where we disagree is on the solution."

Rudenstine, who has refused to negotiate with the protesters, described the sit-in as "inconsistent with the fundamental principles of an academic community." He recently announced his intention to form a university-wide committee to reconsider all aspects of the wage issue -- a proposal that the students considered unsuitably vague.

There are no plans to discipline or evict the students unless health or security concerns arise, Wrinn said. Unlike Harvard anti-war protesters of the Vietnam era, the current demonstrators have pledged not to obstruct access to the building or damage property, and their behavior has helped earn them support.

Food and toiletry essentials are delivered, but no written materials are allowed inside the locked building, prompting some professors to hold classes on the grass nearby for the benefit of cloistered pupils. Supplies are neatly stacked against the walls, and laptop computers, press contact lists and cell-phone chargers allow the media-savvy contingent to update their Web site and juggle queries from parents as well as Italian National Radio and ESPN.

A recent Harvard Crimson poll of about 372 undergraduates showed that 53 percent support a living wage. Half of the respondents said the sit-in was "not justified," however, and only 44 percent of those who support a living wage said they would support that pay level if it meant a tuition increase.

Support for the cause, if not the tactics, has been strong. Hundreds of faculty members urged the university to reconsider its wage policy in a full-page newspaper ad, and dozens of university workers have held solidarity rallies and marches for those speaking out on their behalf.

"We'd be dead without them," said Frank Morley, 60, a contract custodian at Littauer Hall who dips into a retirement account to supplement his $10-an-hour pay. "Put it this way, not too many folks pay attention to janitors. Universities pay attention to students: It's their bread and butter."

Protesters have received endorsements from Cambridge natives Ben Affleck and Matt Damon, as well as actor Warren Beatty, Jesse Jackson, former labor secretary Robert B. Reich, Sen. Edward M. Kennedy (D-Mass.), Rep. Barney Frank (D-Mass.), filmmaker Michael Moore and the rock band Rage Against the Machine, among others.

"Workers who give their all every day should not be rewarded with poverty wages, and especially not from the wealthiest school in the country," said AFL-CIO President John Sweeney, who spoke here while in town for a labor conference.

Not everyone is so supportive. The Harvard Crimson has backed higher wages for workers, but criticized the occupation as "unjustified and ineffective." Some faculty and students have called for it to end. Still others, caught in the academic crunch, are not sure what to make of it at all.

"I definitely support Harvard giving $10.25 an hour to the dining hall workers," said Leslie Munoz, 21, a junior from Pueblo, Colo., as she flipped through a book on the library steps Thursday. "But I'm not an economist, and I don't know if it's feasible."

Harvard law student Ashwini Sukthankar talks to passersby from building occupied by protesters since April 18.Harvard students and faculty join hands for a moment of silence last Monday during demonstration for higher pay for custodians and cafeteria workers.