This paper reports on the development, psychometric properties, and validity of a self-report measure designed to assess potential stressors among staff in services for people with intellectual disabilities, the 33-item Staff Stressor Questionnaire (SSQ). A questionnaire including the SSQ and scales measuring staff outcomes was administered to 512 staff across seven services for people with intellectual disabilities. The SSQ was factor analyzed to produce seven subscales reflecting different potential stressors for staff: user challenging behavior; poor user skills; lack of staff support; lack of resources; low-status job; bureaucracy; and work-home conflict. The SSQ subscales showed adequate internal reliability in terms of Cronbach’s alpha and mean inter-item correlations. Associations between SSQ subscale scores and different staff groups, and patterns of associations between SSQ subscales and a range of staff outcomes, provided evidence suggestive of the face-, construct-, and criterion-related validity of the questionnaire. The SSQ shows promise as a measure for assessing potential stressors for staff in services for people with intellectual disabilities. Further studies to examine the reliability, validity, and utility of the SSQ are recommended.