Thi s study examined relationships between three factors related to teacher self-effica cy (use of inclusive instruction, collaboration with others, and managing disruptive behaviour) and practicing teachers’ sentiments, att itudes, and concerns about inclusive education of students with developmental disabilities. We calculated Pearson product-moment correlations to examine individual associations and conducted a series of multiple regression analyses to determine which associated factors, when considered simultaneously, were most predictive. Results indicated that higher self-effica cy for collaboration was the only predictor associated with more positive sentiments and att itudes and with fewer concerns about inclusive education for students with developmental disabilities. The r esults replicate the find ings of a previous study on this topic and highlight the importance of both pre- and in-service education aimed at providing educators with dispositions and skills related to effe ctive collaboration with parents and other members of a school-based team. ISSN 1918-5227 Pages 18- 32 Follow this and additional works at: htt p://ir.lib.uwo.ca/eei