Sven Mislintat joins the Gunners after a decade of service at the Bundesliga side, where he worked as head of recruitment.
Dortmund told Sportsmail on Monday that they were unable to stop Mislintat leaving.
‘We would have liked to keep him,’ said a Dortmund spokesperson. ‘He has been doing great scouting work with Zorc over the last ten years. He helped and improved scouting at the club, made it more professional.
‘We have a very good relationship with him and because of what he achieved, we decided this morning that we would release him.’
He will work closely with Arsenal manager Arsene Wenger and chief executive Ivan Gazidis. The north London club have also confirmed that Steve Rowley has left his position as chief scout after 25 years.
Wenger has said he is hoping that Mislintat will help the club identify top transfer targets in the future.
We are delighted that Sven is joining us,’ Wenger said. ‘Identifying and developing talent is a core part of our philosophy and Sven has an outstanding track record over many years. We look forward to him taking our existing recruitment approach forwards.’
Wenger thanked Rowley for his work and labelled him as a ‘key figure’ over the years.
He added: ‘We would like to thank Steve Rowley for all his hard work over many years for the club.
‘He has been a key figure in our recruitment of so many top players and has travelled thousands and thousands of miles, watching hundreds of games for us during his time at the club. We wish him well for the future.’