The present paper forms part of the High Secure Psychiatric Hospitals’ Nursing Staff Stress Survey and explores the causal role of generalized and specific stress resistance resources (SRRs) in the stress process following physical assault. Confidential self-report questionnaires were administered to all nurses working in English and Scottish High Secure Psychiatric Hospitals. A total of 636 nurses responded to questionnaires on physical assault, other relevant stressors, SRRs, and psychological distress as measured by the GHQ-12. Data were analysed using univariate and multivariate hierarchical regression analysis. Self-esteem, self-confidence, and coping met the definitional criteria of generalized SRRs. Findings on social support from outside work suggested a mediating role of this variable. Furthermore, manager support could be identified as a specific SRR that moderated effects of physical assault on psychological distress: assaulted nurses having a supportive manager scored lower on psychological distress than non-assaulted nurses having an unsupportive manager. It is concluded that, at a conceptual and empirical level, the current approach yields advances in terms of how generalized and specific SRRs contribute comparatively to alleviate high levels of psychological distress by testing additive, mediator, and moderator models, thereby achieving an increase in explanatory power of the stress process model as compared to previous research.