The charismatic German has been in charge of the club since 2008, but announced at a press conference earlier today that this campaign would be his last.
His contract had been due to run until 2018, but following a difficult season he requested an early termination. "It's not that I'm tired, I've not had contact with another club but don't plan to take a sabbatical.
"I always said in that moment where I believe I am not the perfect coach anymore for this extraordinary club I will say so.
"I really think the decision is the right one. This club deserves to be coached from the 100% right manager."
Dortmund are currently 10th in the Bundesliga having spent much of the season in and around the relegation places, but he'll more likely be remembered for the two league titles and 2012 Champions League final appearance delivered during his time in charge.
Speculation has already begun regarding his next move, with Man City seen as the most likely destination. You can never tell what Real Madrid are planning either but one thing's for certain, he'll not be short of offers.