While the placement of students with complex learning needs in Canadian classrooms may be mandated in policy, the development of inclusive-positive practices requires direct, and at times delicate, support and encouragement from principal teams. Without genuine engagement and buy-in from teachers and school staff, students in inclusive classrooms may not find meaningful opportunities in those spaces. Often, it falls on principals to be leaders of attitudes and practices so that inclusive school communities can thrive. Fortunately, the framework of self-determination theory provides a path by which principals can catalyse attitudinal changes (autonomy), best practices (competences), and enriched community relationships (relatedness). This study includes the questionnaire responses of 275 principals (and vice principals) from six provinces in Canada. Of those 275 participants, 46 principals also participated in interviews. The findings of this study suggest that affecting attitudinal changes requires specific and comprehensive practices. Principals also need to model inclusive-positive attitudes in their behaviour and practice. Finally, the careful curation and maintenance of relationships is a necessary for the well-being of the school communities. Implications for principal practice and school well-being are included.