Introduction: The second victims are those professionals who, when faced with a mistake, are traumatized, questioning their professional and personal skills. Knowledge of their experience allows institutions to understand the consequences of error in professionals to carry out care actions for the professionals involved, improving care security. The objective of this study is to characterize the phenomenon of second victims and to know the perceived support measures., Method: Cross-sectional descriptive observational quantitative study. Health professionals from five highly complex institutions participated through convenience sampling. The data collection instrument was the Second Victim Experience and Support Tool (SVEST) validated in Argentina, composed of impact dimensions (psychological, physical and professional skills) of support received (colleagues, supervisors, institutional and measures not related to the workplace) and two outcome dimensions (professional abandonment and absenteeism)., Results: 1134 professionals participated and 56% said they had made a mistake. The mean STEVS was 2.5, with the psychological impact dimension predominating (x = 3.4). As part of the support measures, professionals perceived greater support from family and friends (not related to work) (x = 3.1). The greater the impact, the lower the perception of support measures (Rho: -0.8, p = 0.047)., Discussion: More than half of the professionals refer to being second victim with a significant psychological impact, who, despite working in institutions that have patient safety protocols, received support from nonwork-related environments.