Previous research shows that collegial conversations and co-assessment can contribute to increased equivalence in assessment and grading. The purpose of the present study is to investigate how music teachers who are active in upper secondary schools express themselves about their experiences of equal assessment and grading and how they believe that the collegial knowledge among subject teachers in music affects them in their work with equal assessment and grading. To investigate this, a qualitative study has been done with e-mail interviews as a data collection method. Four music teachers aged 27–33 years participated in the study. The results show that all music teachers in one way or another take part in collegiate conversations or joint assessment. There are differences between the teachers about how they can share the thoughts and experiences of other music colleagues. For some of the teachers, there are opportunities for collegial conversations and joint assessment at the school, as well as opportunities for subject meetings in the municipality. For one of the participants in the study, there are no organized meetings for music teachers to meet and talk.