Born in Baltimore and raised in the Sugar Hill section of Pennsylvania Avenue and on Gwynns Falls Parkway, she was the daughter of Franklyn Thomas Williams, a postal supervisor, and Lucille Elizabeth Talbott Williams, principal of the Fannie Coppin Demonstration School. Mrs. Hillery attended Gwynns Falls Elementary School and Pimlico Junior High School and was a 1961 graduate of Western High School. Family members said she was one of the early African-American graduates of the school.
She studied mathematics at Morgan State University and earned a Bachelor of Arts degree at Notre Dame of Maryland University. She was a member of the Delta Sigma Theta Sorority and was recently honored for her 50 years of membership.
"Carol had an analytical mind. She was very sharp. And with her, things had to be right, almost perfect," said Barbara Forrest, a cousin who lives in Owings Mills. "She was also a fighter to the end. She was a positive person who was friendly and caring. Her faith was strong."
Mrs. Hillery taught in Baltimore City public schools for several years but changed careers and became a software engineer. She joined Westinghouse Defense Electronics in Linthicum and worked on radar and air traffic control systems.
"She sat by the coffee pot and I used to visit it all the time," said her husband, Joseph Francis Hillery, a software engineer at Northrop Grumman. "There was something special about Carol. She played bridge at lunch and so I learned to play too. I could never equal her. She was the best natural bridge player I've ever met."
She left Westinghouse and joined Computer Services Corp. in Rockville, where she also worked on a new generation of air traffic control software. She subsequently joined the Space Telescope Science Institute, located on the grounds of the Johns Hopkins University.
Nearly 25 years ago she helped with code configuration management used in the correction of a minor imperfection in the primary mirror on the Hubble Space Telescope. That mirror had been ground to the wrong shape. She was part of a team that supported the optical correction.
"Carol was an organized and exacting person," her husband said. "She knew the right way and did not deviate. There was something about her that made everyone love her. There was no ambiguity with Carol. In any situation, you knew where she stood."
She left the Space Telescope Science Institute and became an administrator at Nativity Network Schools in Mount Vernon. The schools, which include the Saint Ignatius Loyola Academy, educate urban students. She visited other cities and worked in event planning and created a website.
She also worked in sales part time at the Nordstrom Towson store's Encore women's clothing department. Family members said she developed relationships with her repeat customers and advised them on fashion.
Mrs. Hillery belonged to several bridge clubs and played regularly. She was a president of the Baltimore Congress of Bridge Clubs, a division of the American Bridge Association. She was national president of the Holidays Inc., a social bridge organization, as well as a past president of its Baltimore chapter.
She also enjoyed wagering at casinos and travel. She and her husband took bridge-themed cruises. She had recently been to Croatia. She was also a bargain shopper and did not like to pay full price.
A Mass of Christian burial will be offered at 10:30 a.m. Thursday at St. Ignatius Roman Catholic Church, 740 N. Calvert St., where she was a member, Eucharistic minister, lector and liturgical scheduler. She also ran a program for adults entering the church.
In addition to her husband of 30 years, survivors include a daughter, Cydney E. Rolle of Roswell, Ga.; a sister, Joanne E. Williams-Cooper of Fairburn, Ga.; and a granddaughter.