As Director of Football, Jeff will have a wide-ranging brief. He will organise the recruitment strategy and offer support to the manager in identifying and signing the right players.
Jeff will provide backing for the medical, sports science and welfare departments, as well as work closely with the Academy, helping to develop and enhance the pathway for the Club's promising youngsters.
"It is an honour to be given this opportunity to work at such a great football club, with a lot of tradition and a great fan base," said Jeff.
"Football is my life and to be part of this new project, to help push the Club forward, is an exciting challenge."
Jeff, 50, brings a wealth of experience and expertise to the Club in a variety of areas including player recruitment, scouting, coaching and associated technical aspects.
Jeff, who is highly regarded by one of his former clubs Real Madrid, is multi-lingual with a host of worldwide contacts and an encyclopaedic knowledge of players.
A former apprentice at Luton Town, his first coaching role was with his home-town Hatters, delivering for Football in the Community and then their Centre of Excellence.
After a stint in America, it was off to Charlton Athletic as Under-16s/17s coach before a move to Rushden and Diamonds as head of youth development/youth coach.
It was then back to Charlton where Jeff was head of international scouting for six years before becoming chief scout.
Alan Curbishley took him to West Ham United for a short spell as technical co-ordinator before he was quickly snapped up by Real Madrid.
Jeff spent four months at Madrid under technical director, Miguel Angel Potugal, identifying and scouting young players for the Spanish giants.
Two of the principle targets he was tracking at that time were Karim Benzema and Luka Modric, both of whom now star for Los Blancos.
In 2008, Jeff joined Newcastle United as technical co-ordinator and spent more than two years at the club before taking a position as Aston Villa chief scout in November 2010.
A UEFA A licence coach, Jeff was at Villa Park for five months working with Gerard Houllier before a return to Charlton in 2011 as technical director.
Either side of a six-month spell at Fulham as senior European scout, Jeff did consultancy work for the Premier League.
* Blues have parted company with Football Consultant Ewan Chester. His contract is not being renewed and the Club thank Ewan for his services.