Walewein Witten started working with singers at the age of 17, in a baroque opera at Dartington Summer School. From this moment his love for the human voice and for vocal music always urged him to work with singers. His natural feel for the singing voice, and his own vocal studies make him a highly valued accompanist and vocal coach.

In 2000 he worked as a repetiteur at the Liceu Opera House in Barcelona in the production of The Magic Flute. As a freelance repetiteur in Holland (2000-2005) he assisted productions of John Adams Nixon in China, and Strauss' Die Fledermaus, and worked as a private vocal coach. As a principal harpsichordist of the Utrechts Barock Consort he performed many baroque operas.

Walewein made his first conducting experiences at the harpsichord. His repertoire included concertos (for 1 to 4 harpsichords) by Bach and his sons, and also many orchestral pieces from the French, German and Italian baroque era. Conducting from the harpsichord he played the solo parts, as well as thorough bass. Also he performed Mozart piano concertos in E flat major and d minor leading the orchestra from the keyboard.

From 2005 to 2014 Walewein Witten worked as a repetiteur/assistant conductor at the opera theatres of Düsseldorf, Bremerhaven and Kassel. In this period he obtained an extensive repertoire of more than 70 operas, reaching from the Baroque era to contemporary music.  From 2005-2007 he studied orchestral conducting with Prof. Lutz Herbig in Düsseldorf and continued his studies with George Hurst and Denise Ham in Canford/Bournemouth.

As an assistant conductor he worked in several summer festivals such as Dartington Summer School Festival, Kammeroper Schloss Rheinsberg, Tiroler Festspiele Erl, and Summer Opera Alden Biesen (BE). In 2011 he conducted a student project with Pergolesi La Serva Padrona and Barber A Hand of Bridge at Stavanger University (NO).

Walewein Witten worked as a vocal coach at the Academy of Music and Performing Arts in Frankfurt (Germany) from 2013 to 2018. Besides that he has works as a musical assistant for the opera department at the University of Arts in Berlin since 2015. He assisted in various opera projects there, and worked as a guest professor for vocal coaching in the academic year 2016/2017.