The Swede initially joined the Gunners as a 21-year-old midfielder and spent nine seasons with the north Londoners, making 216 Premier League appearances and winning two titles, one of which came for the unbeaten "Invincibles" side of 2003/04.
His journey with the club has since continued in a coaching role.
In 2016/17 Ljungberg was involved with the Youth Development phase of the academy and last summer he took charge of the Under-23 team featuring Eddie Nketiah and Reiss Nelson that had just won the 2017/18 Premier League 2 Division 1 title.
He has now made another step up, becoming the assistant first-team coach as part of a new "transition team" seeking to aid the pathway for youngsters into Unai Emery's squad.
And he is determined to ensure that the club's young talents are able to keep moving forward at Arsenal in the same way that he has.
"I'm really excited by this opportunity to continue helping develop and work with some of the great young players we have coming through in the first-team environment, and to work alongside Unai and his coaching team to help Arsenal win trophies," Ljungberg told Arsenal’s official website.
"I'm looking forward to working in this new structure and to pass on my experience and knowledge about what is needed to succeed at this level."
Two other former Arsenal players will also be heavily involved in helping the club's academy players fulfil their potential.
"I have always had a deep commitment to developing young players and am delighted to be back working in an area which is so important to the future of our club," said Bould.