Through the years Concerto Copenhagen has collaborated with many international artist like Emma Kirkby, Andreas Scholl, Anne Sofie von Otter, Sonia Prina, Vivica Genaux, Andrew Manze, Andrew Lawrence-King, Reinhard Goebel, Ronald Brautigam, Jordi Savall and Alfredo Bernardini.
Concerto Copenhagen has released recordings on CPO, Deutsche Grammophon and BIS, as well as DVD productions on Harmonia Mundi and Decca.
Mortensen studied with Karen Englund (harpsichord) and Jesper Bøje Christensen (figured bass) at The Royal Danish Academy of Music in Copenhagen and with Trevor Pinnock in London.
As a soloist and chamber musician, Mortensen has toured all over Europe, USA, Mexico, South America, Australia, China and Japan.
Mortensen was professor of harpsichord and performance practice at the Hochschule für Musik und Theater in Munich from 1996 to 1999.