Background. A growing body of empirical evidence suggests that organisational factors are more important than classroom specific issues in determining teacher morale. Accordingly, it is necessary to have available measures that accurately assess morale, as well as the organisational factors that are likely to underpin the experience of morale. Aim. Three studies were conducted with the aim of developing a psychometrically sound questionnaire that could be used to assess teacher morale and various dimensions of school organisational climate. Sample. A total of 1,520 teachers from 18 primary and 26 secondary schools in the Australian state of Victoria agreed to participate in three separate studies (N = 615, 342 and 563 in Studies 1, 2 and 3, respectively) that were used to develop the questionnaire. The demographic profile of the teachers was similar to that found in the Department as a whole. Method. All teaching staff in the participating schools were asked to complete a self-report questionnaire as part of the evaluation of an organisational development programme. Results. A series of exploratory and confirmatory factor analyses were used to establish the questionnaire's factor structure, and correlation analyses were used to examine the questionnaire's convergent and discriminant validity. Conclusions. The three studies resulted in the 54-item School Organisational Health Questionnaire that measures teacher morale and 11 separate dimensions of school organisational climate: appraisal and recognition, curriculum coordination, effective discipline policy, excessive work demands, goal congruence, participative decision-making, professional growth, professional interaction, role clarity, student orientation, and supportive leadership.