Frank C. Carlucci was sworn in as secretary of defense Monday and was praised by President Reagan as an insider who knows how to get results from Congress and the bureaucracy.
Carlucci, who has been Reagan's national security adviser, succeeds Caspar W. Weinberger, who resigned earlier this month because of his wife's health.
Carlucci placed his hand on a Bible held by his wife, Marcia, as the oath of office was administered by federal appeals Judge Laurence Silberman in the Roosevelt Room of the White House. Weinberger was among the guests.
Reagan told Carlucci that he would face "extraordinary challenges" to strengthen military preparedness.
Carlucci thanked Reagan for the tone he set in their relationship. "You have made a tough job seem easy. I also want to thank you for your willingness to tolerate my viewpoint even when you've known that it has not accorded with yours."