Effective media education requires that teachers have sufficient media literacy competencies as well as the competencies to promote media literacy in students. This article describes the development of a questionnaire to measure these competencies individually or as a team. The questionnaire was developed in five stages. A systematic and critical listing of existing inventories resulted in a preliminary questionnaire. In the final stage, the questionnaire was submitted to a representative sample of 454 teachers and 219 student teachers, and an exploratory factor analysis was conducted. The results show that the questionnaire is sufficiently valid and reliable.