In the 18 years under Witsch's leadership, the Kiepenheuer & Witsch publishing house released more than 600 books, showcasing a remarkably broad and innovative program of fiction, non-fiction, and academic works. Early on, Witsch attracted important exiles such as Joseph Roth, René Schickele, and Erich Maria Remarque to his publishing house, providing the audience with access to long-missed foreign-language literature through authors like Saul Bellow, J.D. Salinger, Georges Simenon, and many others. Witsch also focused on young German authors, from Heinrich Böll to Rolf Dieter Brinkmann and Nicolas Born, deliberately avoiding any contact with Group 47. Through his socio-political non-fiction and academic books by Wolfgang Leonhard, Ralph Giordano, and Hans-Ulrich Wehler, Witsch significantly influenced public opinion. As a successful entrepreneur, Witsch was also mindful of the changes in the book market.