Yes, there is a piano in the Main Auditorium, but it is reserved only for performances/concerts. If you are interested in organising such a performance, please contact the Staff Association (Staff.Association@cern.ch). If you would like to practice, you can contact the Jazz Club (Vice-President and Secretary Marc Vanden Eynden: Marc.Vanden.Eynden@cern.ch) which has two upright classical pianos, or the Learning classical music club (LCMC-info@cern.ch) which also has a piano.