Secretary of State Hillary Rodham Clinton made a surprise return to her alma mater on Monday, picking up an honorary degree from Yale University 36 years after earning her law degree from the Ivy League school.

Graduates celebrating commencement at Yale erupted in cheers as Clinton was introduced. In keeping with Yale tradition, the names of honorary degree recipients are a closely held secret, although word began trickling out Sunday of Clinton's participation.

Clinton did speak for about five minutes during the Yale Law School's separate commencement event held in the early afternoon. There, the 60-year-old Clinton reminisced about her days at Yale, saying the law school was an "encampment for protests and frivolity" when she arrived in the fall of 1969.

She met her future husband, Bill Clinton, at the school the following year, 22 years before he was elected the nation's 42nd president.

She expressed hope that every graduate would "use every creative gene you have" in order to work "on behalf of the public good."

Clinton drew laughs from the crowd when she jokingly apologized for taking Yale Law School Dean Harold Hongju Koh "away from the law school and putting him to work in Washington." Koh was nominated by President Barack Obama to be legal adviser to the State Department, and remains a possible nominee to the US Supreme Court.

In a nod to the rough job market, Clinton also urged the new law school graduates to apply for work in the Obama administration, at the State Department and with the United States Agency for International Development.

Koh said after the law school ceremony he hoped his students learned from Clinton "what is possible to achieve in one lifetime."

"Everyone who got the honorary degrees were in these seats not that long ago," Koh said. "And you know, what they know is, they could be a mother, a lawyer and US senator, Secretary of State, presidential candidate. There's no limit. That's what they should think. There's no limit to what they can do."

Clinton spoke to Yale graduates once before, in 1991 when she gave the traditional Class Day speech, which is the major address to graduating seniors held the day before commencement. This year's Class Day address was delivered Sunday by author Christopher Buckley, a 1975 Yale graduate.

Sculptor Richard Serra, Nobel Prize-winning economist Thomas Schelling and Pulitzer Prize-winning writer John McPhee were among the others receiving honorary degrees from the university Monday.

(Agencies)