This study analysed the teachers and hearing and speech specialists' (HSSs) attitudes towards and knowledge of sustainable inclusive education for children with hearing loss in the Canary Islands. The study sample comprised 297 teachers and HSSs. The authors designed the Inclusion Questionnaire (InQ). It was found that teachers and HSSs' attitudes and knowledge centred on seven attitudes: sustainable professional development, self-efficacy in teaching competencies, inclusive leadership, assistive electronic technology, challenges around family involvement, embedding and sustaining reflexive practice, and technological usability and universal accessibility. The alpha coefficient for the total InQ was 0.841. These InQ factors have been developed with reliability and logical validity. There were differences in items under three factors among female and male teachers and HSSs. Teachers and HSSs also showed differences in the variables of age, work experience, and professional experience with students using hearing devices. Recommendations for inclusive values and sustainable educational change are suggested.