Background: Professionals working with trauma victims can experience both negative and positive effects following exposure to secondary trauma. The aim of the study was to determine the relationship between secondary traumatic stress (STS), secondary posttraumatic growth (SPTG) and cognitive coping strategies and to establish the mediating role of cognitive coping strategies in the relationship between STS and SPTG. Material and Methods: A group of 500 professionals working with trauma survivors were surveyed. The Secondary Traumatic Stress Inventory, the Secondary Posttraumatic Growth Inventory and the Cognitive Processing of Trauma Scale was used. Results: The results indicated that 29% of professionals demonstrate a high intensity of STS, and nearly 34% exhibit a high level of SPTG. Denial and regret were positively correlated with STS; positive cognitive restructuring, resolution/acceptance and downward comparison were positively related to SPTG. Two cognitive coping strategies, i.e., positive cognitive restructuring and downward comparison, were found to act as mediators in the relationship between STS and SPTG. Conclusions: Understanding the effects of secondary exposure to trauma and the coping responses of professionals working with trauma survivors will support the development of prevention and intervention actions aimed at protecting them from the deleterious impact of exposure to secondary trauma at work and promoting secondary posttraumatic growth. Med Pr Work Health Saf. 2023;74(6):449–60.