Dermot was an active member of St. Vincent de Paul Catholic Church, providing his services to multiple committees over the past 39 years. He took great satisfaction with his involvement in the St. Vincent de Paul Society, where he served as the secretary for 20 years. He was a life-time member of the K of C #414 3rd Degree. He proudly served as secretary/ treasurer of the Ancient Order of the Hibernians. Mr. O'Keeffe was a member of the St. Patrick's parade association, was a past president and led the parade one week late, due to the blizzard in 1973. He was an active volunteer for the American Heart Association and received many honorable awards, including state volunteer of the year for his contributions to promoting ethnic diversity education. He received a key to the City of Bay City for his volunteerism in such community group as the local American Heart Association, for which he served as treasurer and president; participating on the Board of Directors for the United Way for Bay County as well as driving innumerable miles to escort patients to their appointments for the Cancer Society.