The former Wales A coach took up the reins last week as players returned for training after the summer break.
His appointment has been greeted with huge optimism by all those connected with the club, helping to erase the memory of a losing streak lasting 11 games at the end of last season.
Club chairman Len Price said: “Dennis is without doubt one of the top Welsh rugby coaches of the past decade, ranking alongside Mike Ruddock and Gareth Jenkins.
“He will bring to the club a totally professional approach, developing the undoubted talent we already have within the club.
“Dennis is extremely well respected throughout the game and I am sure his appointment will encourage many players throughout the area looking to develop their rugby careers.”
Llanharan, who open their league campaign at home to Blackwood on August 31, also hope to name a new forwards’ coach this week.
