The aim of this study was to analyze the relationship between professional isolation and occupational stress in teachers. A systematic random sample of 1158 French Canadian teachers were administered French Canadian versions of the "UCLA Loneliness Scale and Teacher Stress Inventory." Professional isolation was measured by the subjects' responses on a 4-point scale to 20 statements such as "I feel in tune with people around me." Teacher stress was measured by responses on a 5-point scale to the question "As a teacher, how great a source of stress are these factors to you?" Causes of isolation were identified by the model of causal attribution: causality, stability, and controllability, based on a French Canadian translation of the Causal Dimension Scale. The results indicated a positive and significant correlation between isolation and occupational stress. However, the study failed to confirm its predictions concerning the moderator effect of causal attribution. The results of the study are provided in five tables, each of which is followed by a discussion. (Contains 44 references). (SPM)