As school systems strive to support students with special education needs in inclusive schools, there has been a persistent lack of scholarly literature that addresses the ways in which school principals are engaged in this process. This article is a response to this gap and aims to examine the question: What types of experiences do school principals identify as formational in their support of students with special education needs and fostering inclusive schools? Based on the analysis of data collected from 285 school principals from six provinces in Canada, four key themes are identified including: relationships, modelling behaviours, communication and principal isolation and lack of preparation. These themes are examined with consideration for how to support principals' professional leadership in fostering inclusive schools. As a result, this article's significance is in its examination of the experiences of principals and how these influence their leadership practice for supporting students with special education needs and fostering inclusive schools.