More than a century is passed since Freud conceived the concept of defense mechanisms. In this article, we retrace the historical evolution of the construct and offer a narrative review of current clinical and empirical literature on its relevance in clinical psychology. Conceptual contributions and empirical findings on the relationship between defenses and personality, as well as between defensive styles and psychopathology (e.g., eating, depressive, and personality disorders) were described. Findings showed that defense mechanisms can help clinicians in understanding the function of patients' symptoms and in tailoring therapeutic interventions. Lastly, we reviewed studies on the potential role of defense mechanisms in unpredictable and changing environmental conditions, such as the outbreak of Covid-19 pandemic. All these studies support the view that defensive functioning is a key topic in the mental health field, and that the further application of reliable and clinically relevant assessment tools is a pivotal future direction in both research and clinical practice.
Keywords: defense mechanisms - historical evolution- clinical psychology.