A 1947 graduate of Northwestern's Medill School of Journalism, Mrs. Trienens served as a president of the Northwestern University Women's Board, an organization she helped found, and on the board of The Alumnae of Northwestern University. She also was a member of Medill's Advisory Board. In 1978, Mrs. Trienens received the Northwestern University Alumni Association Service Award, and she was a former director of the John Evans Club. She was married to Howard Trienens, a partner of the law firm Sidley Austin LLP and former chair of Sidley's executive committee. He is a longtime member of Northwestern's Board of Trustees and was its chairman from 1986 to 1995. Mrs. Trienens, of Glencoe, Ill., had served as vice president of the board of directors for the Peggy Notebaert Nature Museum, a life trustee of the Chicago Symphony Orchestra, president of the Field Museum's Women's Board and president of the Glencoe Garden Club. She also was a member of the Women's Board of the Ravinia Festival and of the garden committee for Millennium Park. Mrs. Trienens, neé Paula Ruth Miller, was raised in Wilmette, Ill., and graduated from New Trier High School. While a student at Northwestern, she met Mr. Trienens, a veteran who had just returned from World War II. They were married in 1946. Mrs. Trienens also is survived by sons, John and Kip; a daughter, Nan Kaehler; nine grandchildren; and two great-grandchildren.