Objective: This research study investigated relationships between factors that influence the experience of psychological stress by staff working in residential services supporting adults with learning disabilities and challenging behaviours. A psychological model was developed that related the personality traits of direct care staff with their personal coping style, behavioural knowledge and emotional reaction when exposed to environmental stressors and investigated the impact on psychological distress experienced. Design: A self-report questionnaire study on sixty-nine direct care staff working in an independent sector community based service for adults with learning disabilities and severely challenging behaviours. Correlation and regression analyses were employed to examine relationships between the different factors. Method: Staff completed a battery of measures including versions of the Eysenck Personality Questionnaire (EPQ-R), Shortened Ways of Coping (Revised) Questionnaire (SWC-R), the General Health Questionnaire (GHQ), Knowledge of Behavioural Principles (KBPAC), Care Staff's Emotional Reactions to Aggressive Challenging Behaviours and Work and Client Sources of Stress Checklist. Results: Staff reported high levels of stress. A significant association was found between Neurotic personality type, the use of wishful-thinking coping strategies, a negative emotional reaction to challenging behaviours and greater levels of psychological distress. No association was found between knowledge of behavioural principles and stress. Discussion: Support was found for the proposed psychological model for staff stress. Clinical implications were discussed that have a direct influence on the way in which staff working in services for people who challenge are supported by clinical psychologists. Suggestions were made for future research in the area.