Foster J. DeGiacomo, 97, a proud United States Marine Corps veteran and longtime Concord resident, died peacefully at his home on February 11, 2022. He was the loving husband of the late Nancy C. (DiMaggio) DeGiacomo who died in 2016. He was born in Boston on September 28, 1924 to his late parents, Foster and Frances (Bruno) DeGiacomo. He graduated from Boston English High School in 1942. Soon after his 18th birthday, Foster enlisted in the Marine Corps, and was called to active duty in March of 1943. After completing boot camp training at Parris Island and advanced training at the Aviation Radio School, Foster was assigned to the 3rd Marine Air Wing at Cherry Point, NC as an Aviation Radio Operator. He was later selected for the USMC officer program and transferred to the University of Rochester. After World War II, Foster was discharged in 1946 with the rank of Corporal. He attended Dartmouth College and, thereafter, Boston University, College of Engineering, from which he graduated with a concentration in aerospace. A retired Aeronautical Engineer, Foster worked for Raytheon for 25 years, designing and building air to air and ground to air missiles. He and his family moved to California where he worked for North American Aviation as a Project Engineer on the Apollo space program's command module. After returning to Massachusetts, he worked for Raytheon and, thereafter, for the United States Air Force at Hanscom for 18 years on the Army-Air Force Joint Stars Airborne Ground Surveillance program. He also taught as an instructor at Northeastern University for many years. A Concord resident since 1965, Foster was a parishioner at Holy Family Parish and a life member of the Concord Rod & Gun Club. He held a private pilot's license and was a long-time member of the Hanscom Aero Club, enjoying many flights in the New England region. Foster is survived by four children, Keith DeGiacomo, Paula DeGiacomo and her husband Blake Godbout, Barbara Moccaldi and Vincent DeGiacomo and his wife Christine, as well as two grandsons, Alex and Kevin DeGiacomo. He was the beloved brother of the late William and Joseph DeGiacomo and Rosemary Nolan. Immediate family and caregivers gathered for his Funeral Mass on Friday, February 18, 2022 in Holy Family Parish, Monument Square, Concord Center. Burial followed at Sleepy Hollow Cemetery, where Officers of the United States Marine Corps presented military honors. Concord's Town Flag flew at half-staff on the day of funeral in honor of Foster's faithful and honorable service to our country during World War II. Arrangements are under the care of Dee Funeral Home & Cremation Service of Concord.