The human response to stress is a homeostatic mechanism allowing adaptation to environmental stressors, involving multiple organ systems and being both adaptive and maladaptive. Acute stress involves an immediate, coordinated body response via the SNS and HPA axis, while chronic stress results from prolonged exposure, leading to dysregulation and health issues. The SNS, known for the “fight-or-flight” response, releases catecholamines (norepinephrine, epinephrine) to promote survival in stressful situations. The HPA axis releases cortisol in response to stress, regulating metabolism, immune responses, and maintaining homeostasis. The cardiovascular response to stress includes increased heart rate, blood pressure, and blood glucose levels, with chronic stress contributing to cardiovascular diseases. Acute stress enhances humoral immunity while suppressing cellular immunity, whereas chronic stress leads to immunosuppression and increased risk of infection and disease. HRV serves as an indicator of autonomic nervous system balance, with low HRV linked to poor health outcomes and increased mortality. Psychological stress can mimic physiological stress responses, with the limbic system, especially the amygdala, playing a key role in emotional and stress responses. Trauma can lead to long-term psychological and neurobiological changes, with PTSD and burnout being common in high-stress professions like trauma care. ACEs are linked to long-term health and psychological issues, with early trauma affecting brain morphology and increasing the risk of substance abuse. Resilience training and stress management workshops are effective, with mindfulness, yoga, and other self-care practices improving stress response and resilience. Hyper-realistic simulation training improves physiological and psychological responses to stress, helping trauma teams perform better in real-life stressful situations. Genetic and epigenetic factors influence individual stress response and resilience, with epigenetic changes being targeted for improving resilience. Measuring cortisol, cytokines, and other biomarkers helps assess stress and resilience, guiding personalized interventions for stress management. Disruption of circadian rhythms exacerbates the effects of stress, making the maintenance of proper sleep hygiene crucial for health and performance. Practical strategies for alleviating stress include individual approaches like mindfulness, emotional regulation, and communication skills training; team approaches such as resiliency training and stress management workshops; and organizational methods like workload and schedule rotations, debriefing sessions, and focus groups.