Professionals who work with victims and trauma survivors are continually confronted with the destruction, horror, and losses their clients have experienced and are therefore susceptible to vicarious trauma (as a result of their empathetic engagement with and cumulative exposure to traumas related by patients) and post-traumatic growth (as a multidimensional process that leads to both changes in beliefs, objectives, behaviors, and identity as a consequence to trauma exposure). Although psychologists have long been aware of these two phenomena, they remain under-researched. The present study examined whether professionals who work with trauma survivors are impacted by vicarious trauma and whether they experience post-traumatic growth. We also looked for possible correlations between the two phenomena. Analyses of responses to the ProQOL (vicarious trauma) and PTGI (post-traumatic growth) questionnaires provided by 163 professionals (mostly legal practitioners and psychologists) within a French nationwide victim-support organization showed that they experience both vicarious trauma and post-traumatic growth and that these two phenomena are closely linked. Further research is now needed to confirm and more clearly define these links. Results also showed that profession, professional experience, and specialized training moderate vicarious trauma and post-traumatic growth. These variables must be taken into account when evaluating the two phenomena and when providing support to professionals but also in conception and implementation of training programs and supervision settings.