A ceremony at Coon Forum on Monday celebrated the opening of a $25 million, 75,000-square-foot addition to Kellogg Graduate School of Management’s Andersen Hall.

“It’s what we needed to fulfill our mission,” Kellogg Dean Don Jacobs said of the addition, which is part of a three-building complex named after Jacobs, who has been dean since 1975. “We were in dire need of space.”

Construction began 18 months ago, according to Kellogg Assistant Dean and Director of External Relations Richard Honack.

The fourth, fifth and sixth floors will hold faculty offices and a section for Kellogg students who are trying to form new companies, Honack said. The first floor features a new 100-seat classroom, while the second floor is dedicated to student study rooms and group rooms.

“We were just cramped for study space for the students,” said Kellogg Assistant Dean Carole Cahill, “so we were always lacking in space for both group and individual study. This will help relieve that a lot.”

First-year Kellogg student Laura Smith, president of the Graduate Management Association, estimated that 200 students, faculty and staff attended the ceremony to hear administration address the student body.

Smith said the additional space was much needed. “At Kellogg, probably 80 percent of our work is in groups, so people are thrilled because the new space is all group study space and quiet study space,” she said.

But Cahill said the celebration didn’t last long. Students could reserve the room for the first time merely one hour after the ceremony, and almost every study room had someone working in it by the time the reception ended.

“(The students) have moved in and act like they’ve been there for 100 years,” Jacobs said. “The students, the faculty and the staff of Kellogg are very pleased, and you can say that in very big, bold letters!”