The purpose of this study was to create guidelines for stress management intervention by investigating the relationship of 12 factors with stress reactions (emotional exhaustion and irritation) and feelings of mastery among Swedish comprehensive school teachers. Data were collected via a questionnaire distributed to 928 teachers in 27 schools. The response rate was 89%. Multiple regressions were conducted on colleague support, cooperation, coordination problems, goal clarity, learning orientation, manager support, negative feedback, positive feedback, pupil misbehaviour, teacher age, work control and perceived work demands, all as independent variables. Perceived work demands was treated as a dependent variable in an additional regression analysis. Teacher stress reactions were best predicted by perceived work demands, pupil misbehaviour and negative feedback. Feelings of mastery were best predicted by learning orientation, positive feedback and goal clarity. In the additional analysis perceived work demands was best predicted by pupil misbehaviour, coordination problems and (low) work control. Practical implications are discussed.