Robert A. Peck will resign as president of the Greater Washington Board of Trade at the end of the year, he said yesterday, after four years leading the regional chamber of commerce.

Peck, 57, said he is considering opportunities in the private sector, likely involving real estate.

"I came into the job thinking it would not be my last job ever," he said. "I'm at an age where I need to stay or go, and for me it was time to go."

Peck was an unconventional choice in 2001, when he was appointed to lead the group that represents the region's corporate sector on issues such as transportation and economic development. He had spent little time working in the private sector. Most of his career was in government as, among other jobs, an aide to Sen. Daniel Patrick Moynihan (D-N.Y.) and commissioner of public buildings at the General Services Administration, where he oversaw the federal government's real estate. He was a Democrat running an organization heavily populated with Republicans and by temperament was more of a blunt-yet-cerebral policy analyst than an archetypical glad-handing chamber of commerce president.

He took the helm of an organization steeped in history; it has been around since 1889, and his predecessor held the job for a generation. Peck made changes, some of which rankled more traditionalist members of the board of directors. For example, he moved the annual Mid-Winter Dinner, the group's premier event, to Thursday night after it had been held on a Friday night for decades.

"Bob had the very difficult assignment of following someone who had been there for 30 years in John Tydings," said Robert M. Pinkard, chief executive of Cassidy & Pinkard and a member of the board of directors. "They were two different personality types."

Peck moved the Board of Trade headquarters from a traditional Washington office building on 20th Street NW, with private offices that, in Peck's view, stifled collaboration and contributed to a stodgy image. It now is based in slick, modern digs on I Street NW with a street entrance, wide open cubicles and an airy feel. Peck names the new offices -- and the symbolism they conveyed -- as one of his big achievements.

Under his leadership, the organization became a significant player on emergency-preparedness issues and persuaded local governments to adopt modest steps to improve traffic flow. Bigger goals, such as creating a dedicated funding source for Metro, have remained elusive.

"He accomplished a lot in a short time as president," said W. Lyles Carr III, senior vice president of the McCormick Group Inc. and one of the Board of Trade's directors. "I'm sorry that he's decided to move on."

Peck's contract expires at the end of the year, though he said he would be willing to stay on until a replacement is found if he is asked to and is not yet needed at his next job.

Outgoing Board of Trade President Robert A. Peck counts the group's move to a new headquarters among his biggest accomplishments.