The 40-year-old joins from SV Elversberg on a contract running until 2028/29 and will officially take up his role on Wednesday, just days after the departure of former director Sebastian Kehl. His arrival comes at a pivotal moment, with Dortmund sitting nine points behind Bundesliga leaders Bayern Munich and already eliminated from both the DFB-Pokal and UEFA Champions League.

Book's appointment reflects a deliberate shift toward fresh thinking. Despite working with limited resources at Elversberg - a club from a town of roughly 13,000 people - he earned widespread recognition for shrewd recruitment and long-term squad building. During his eight years in various leadership roles, Elversberg climbed from the fourth tier to the 2. Bundesliga, narrowly missing out on top-flight promotion in 2025 after a play-off defeat to Heidenheim. They are currently pushing near the top of the second division once again.

Dortmund's managing director for sport, Lars Ricken, made clear that Book had long been identified as the club's preferred candidate. He highlighted not only his track record of promotions but also his ability to develop young talent and create squad value.

"With Ole Book we have been able to bring in our desired candidate," Ricken said. "I've followed his work for a long time and am convinced he is the right fit for us both professionally and personally. We trust him to bring creative and courageous ideas in the transfer market."

That sentiment was echoed by managing director Carsten Cramer, who pointed to Book's ambition and alignment with the club's identity. "We quickly noticed his hunger for success, high ambitions and tremendous team spirit," Cramer said. "Now the task is to shape the future of our club in a bold and successful way."

Book's rise has been rapid since ending his playing career in 2017, when he turned out for clubs including Rot Weiss Ahlen, MSV Duisburg and Wehen Wiesbaden. He joined Elversberg as a scout before becoming sporting director within a year and later stepping up to board level in 2023. Among his standout transfer successes was the signing of forward Younes Ebnoutalib, who scored 12 goals in 17 second-division games before earning a move to Eintracht Frankfurt.

Now, he inherits a Dortmund squad in transition. Established figures such as Julian Brandt and Niklas Sule are set to depart when their contracts expire, while uncertainty remains over the future of defender Nico Schlotterbeck, who is entering the final year of his deal. However, there is some continuity, with Felix Nmecha, Luca Reggiani and captain Emre Can all recently extending their stays.

Book acknowledged the scale of the challenge but also the opportunity ahead. "Borussia Dortmund is one of the biggest clubs in Europe, and I'm looking forward to giving my all here," he said. "I want to play my part in guiding BVB into a successful future."

His tenure begins immediately - and with Dortmund facing both on-field and structural questions, the task of reshaping the club has already begun.

Thomas Tuchel disappointed with Bayern Munich's season