This article explores the predictive ability of empathy (measured by the Interpersonal Reactivity Index), emotional separation (measured by the Maintenance of Emotional Separation Scale), occupational stress (measured by the Work-Related Strain Inventory), and social support (measured by the Multidimensional Scale of Perceived Social Support) on secondary traumatic stress (STS) (measured by the Secondary Traumatic Stress Scale) in hospital social workers. This cross-sectional study used a sample of 121 trauma center social workers who were predominantly master's-level prepared women with an average of 15.8 years' experience. Emotional separation and occupational stress were the strongest predictors of STS, explaining 49 percent of the variance, which suggests that hospital social workers need to be able to emotionally differentiate during work with patients and families and manage organizational stressors to minimize indirect trauma reactions.