Alliance founder Nelson has stepped down to make the most of his retirement after selling his majority stake in the network and packaging company BDS to Pink.
Nelson said: “Whilst, in many ways I am sad to be leaving the mortgage sector, I do feel that I have managed to make a contribution over the years through my involvement with and the development of PMPA.
"Although the market has changed dramatically, the packaging sector needs the demonstration of professionalism more than ever before, so PMPA will continue to fulfil this vital role."
PMPA chairman, Vic Jannels praised Nelson's achievements, adding: “I would like to thank Ian on behalf of PMPA and the wider packager community who all owe him a debt of gratitude for the raising of standards which he has vigorously continued to promote over the years. We will miss him greatly.”