"It is a fantastic opportunity but obviously with a heavy heart that I leave my post with ND. Only something like this or elsewhere with an international team would have dragged me away," Pamment said.
"At this stage of my career it is exciting and stimulating and I can't wait to get going. I was up there last week for a pre-auction camp and spent some time with Mahela. Obviously he was a very impressive international cricketer and I sense he is a very impressive coach."
Some of Pamment's charges at the Knights may end up playing at Mumbai, depending how the player auction goes.
"Some of the Northern Knights boys were discussed around the table last week when we were talking about potential make-up of recruits. Tim [Southee] was there last year and Cory [Anderson] has been there in the past."
Pamment will be working as a development coach outside of the IPL which is a role he has performed with much success at Northern Districts.
"I will be working with some of the promising guys coming through not just the IPL guys. I have committed myself to working 115 days a year for Mumbai Indians of which 70 are going to be based around the IPL and the others days are around the development of players which is something I have always been really keen on."
Northern Districts Cricket chief executive Ben MacCormack wishes Pamment well in the next stage of his career.
"James has been a key part of the Northern Districts family for a number of years, and has great respect from the players and the ND community as a dedicated leader, a passionate promoter of cricket and extremely efficient administrator.
"We are thrilled that his time here has led to the opportunity with the Mumbai Indians and wish him and his family all the best."