In three seasons as head coach in Oshawa, Smith compiled a record of 135-53-3-13 and earned the honour of the OHL's Coach of the Year after guiding the Generals to a 42-20-0-6 record in 2013-14. Oshawa finished with a 51-11-2-4 record during their championship season in 2014-15.

Before his time in Oshawa, Smith spent six seasons as an assistant coach with the OHL's Windsor Spitfires. During his tenure in Windsor, the Spitfires captured back-to-back Memorial Cup championships in both 2009 and 2010.

Smith has also played professionally, appearing in 45 career NHL games as a defenceman with both the Maple Leafs and Colorado Avalanche after being selected with the 41st overall pick by the New York Islanders in the 1995 NHL Draft.

He also spent parts of nine seasons playing in the AHL with the St. John's Maple Leafs and the Hershey Bears. A native of Windsor, Ontario, Smith played his junior hockey with his hometown Spitfires from 1994-97.

"D.J. Smith is a winner. We believe he is the best person to drive the development and success of the Ottawa Senators," said general manager Pierre Dorion. "D.J is a great communicator and an exceptional strategist. His passionate approach, coupled with his ability to teach the game, is exactly what we were looking for throughout the process. We're thrilled to welcome D.J. and his family to Ottawa."