My purpose with the envisaged study was to determine the effect a critical incident have on employees and how their functioning, psychosocially and at work is affected. Furthermore the goal was to determine if the employees who was affected by a critical incident was exposed to Critical Incident Stress Management (CISM) intervention, and if so did it have an impact on their functioning ( Psychosocial and work performance). An extended literature study was conducted to comprehend the meaning of trauma, the different facets of trauma, how it can impact on an emotional, physical, cognitive and behavioural level. The literature study further focused on the impact of a critical incident on the work performance and family life of the employee. Attention was given to the models in CISM intervention, the role of Employee assistance programs as well as the perceived outcomes of interventions the respondents were exposed to. In the study, data was collected in a qualitative as well as a quantitative manner. In the quantitative study two questionnaires were used as tool to collect information. In the qualitative study the researcher used clinical case notes as part of the document analysis as well as a semi structured interview with both the employee as well as the manager as data sources. Respondents (therapists) were selected according to the probability sampling procedure for the quantitative study and respondents volunteered to participate in the qualitative study after participating in the quantitative study. Participation in the study was voluntary and the participation rate in the quantitative study was 67.5% and in the qualitative study 22.22% It was evident from the study that employees were affected by a variety of critical incidents divergent in severity, circumstances and duration. The impact on each individual was unique and responses ranged in terms of severity. It was evident from the study that employees were affected by the critical incident and subsequently their work performance and psychosocial functioning was affected. The study managed to provide sufficient evidence on the impact of the critical incident on the psychosocial functioning and work performance of the employee. The research proved that individual counselling is effective in working through the incident and improving the psychosocial functioning and work performance significantly. The study also proved that intervention in the form of defusing, debriefing, individual counselling and aftercare is effective in addressing employees' reactions, supporting them to recover emotionally from the critical incident and improving their psychosocial functioning and subsequently their work performance. Conclusions and recommendations were made in terms of the empirical findings. The researcher hope that these conclusions and recommendations will be of value and contribute to the study field of CISM and EAP and have a positive impact on employees exposed to critical incidents and their recovery process.