Dr. Donald E. Lencioni, 78, of Concord, Massachusetts, passed away in his home on May 12, 2019. The youngest of five children, Don was born to Cecil and Assunta Lencioni on August 18, 1940, in Chicago, where he spent his childhood. After graduating from DePaul University, Don went on to earn his PhD in physics from the University of Wisconsin–Madison. There, he met and fell in love with Alice Anacker, who became his wife of 49 years. He spent his career at MIT's Lincoln Laboratory, working on a range of projects, including those sponsored by NASA and the Department of Defense. Don enjoyed traveling, grilling, watching sports, and spending time with his family, especially his three grandchildren. He will be remembered for his kindness and intelligence. He is survived by his loving wife, Alice; his sons, John and Michael; their wives, Jennifer and Anuja; his grandchildren, Emeric, Christopher and Adrian; his brother Livio; his sister Mary and her family; and his late sister Livia's family. Family and friends will gather for visiting hours on Wednesday, May 15th from 5 to 8 pm in the Dee Funeral Home, 27 Bedford Street, Concord Center. His funeral service will be held in the Farrar Chapel of the Dee Funeral Home on Thursday, May 16th at 11 am with Fr. Mark Mahoney officiating. Burial will follow at Sleepy Hollow Cemetery in Concord. Arrangements are under the care of Dee Funeral Home & Cremation Service of Concord.