Former Wyoming Senator Alan K. Simpson will head up the new guard of leaders at the Institute of Politics (IOP) this semester, following the resignations in late December of the two top staff members, Director Phil R. Sharp and Director of the ARCO Forum Heather P. Campion.

Campion, who is also the Associate Director of the IOP, gave notice that she will leave the organization at the end of January to become a senior vice president at Citizens Financial Group in Rhode Island.

Sharp, who served in the House of Representatives for Tennessee before coming to Harvard, resigned his post two weeks ago. He will continue to teach at the Kennedy School of Government.

After serving as the IOP director for more than two years, Sharp said that he decided to step down from the position to devote more time to teaching at the Kennedy School and toward and Environmental Protection Agency on which he serves.

"I'm just eager to get back to more teaching," said Sharp, who has worked as IOP director since 1995. "There's a number of other things that I'm interested in doing."

Simpson, who retired from the Senate in 1997 after three decades in politics, will become director of the IOP at the end of this semester.

But Sharp said that his involvement in the IOP will not end when Simpson assumes the post. He will join the IOP's Senior Advisory Committee.

"I think that the Institute of Politics is a terrific institution," he said. "In my letter [of resignation] to the dean I just was very positive about the Institute of Politics and in particular the students in it who are really extraordinary."

Simpson taught at the Kennedy School last spring as a visiting lecturer. He will continue to hold the Lombard Chair at the Shorenstein Center on Press, Politics and Public Policy in addition to his IOP position.

Simpson could not be reached for comment yesterday.

In an interview, Campion said after seven years at the forum and 15 years at the Kennedy School, it was time for her to move on.

"I thought it one of the greatest opportunities that one could ever have in a professional career," she said.

Campion said she hopes to continue an association with the IOP in some capacity, she said.

Campion has been instrumental in ensuring top speakers for the ARCO Forum, including headline-makers such as Senators Richard A. Gephardt (D-Mo.) and John McCain (R-Az.), who spoke this semester.

In addition, the new Chairman of the Joint Chiefs of Staff Henry H. "Hugh" Shelton, chose the Forum for his first major public address.