This study examined the experiences of 65 behavior interventionists (BIs) who provide 1:1 home-based instruction to children with autism in two Canadian provinces. Dependent variables included occupational stress; the relationships among stress, strain, and coping; the relationship between stress and the characteristics of both challenging families and children with autism; and the most and least rewarding aspects of BIs jobs. The two most stressful work roles for BIs were role overload (the extent to which job demands exceed personal/workplace resources) and role boundary (the extent to which the individual experiences conflicting role demands at work). Significant relationships were found between coping and both stress and strain; however, coping did not moderate the relationship between stress and strain. Significant correlations were found between BI stress and both sensory-related behaviors and social unrelatedness in children with autism. The implications for the BIs, the families, and the agencies are discussed. (Contains 2 tables.)