Dick Advocaat has joined Feyenoord as an advisor to coach Giovanni van Bronckhorst and will work for free until the end of the season.
The experienced Advocaat, 68, has been out of work since leaving Sunderland in October 2015 and his duties at De Kuip will include "observing training sessions and matches and holding meetings with the relevant parties". He will not, however, sit on the bench during games.
"When [technical director] Martin van Geel approached me on Monday morning asking if I wanted to take on this role I immediately had a positive feeling about it," Advocaat told Feyenoord's official website.
"That feeling has only grown after a number of meetings. I'm doing this first and foremost because I have a bond with Giovanni."
Advocaat has won domestic titles with Rangers, where he coached Van Bronckhorst, Zenit St Petersburg and PSV in a distinguished career which has included two spells in charge of Oranje as well as stints with the national teams of South Korea, Belgium, Russia and Serbia.