Functional neurological disorder (FND), previously known as conversion disorder, is a complex condition characterized by neurological symptoms without an identifiable organic cause. These symptoms, which can include motor, sensory, or cognitive disturbances, are not intentionally produced and vary in severity. Diagnosis relies on clinical evaluation and the exclusion of other medical or psychiatric conditions. Treatment typically involves a multidisciplinary approach addressing both neurological symptoms and underlying psychological factors through medical management, psychotherapy, and supportive interventions. Recent advances in neuroimaging and research into FND's epidemiology, pathophysiology, and clinical presentation have provided new insights into the disorder. This review highlights the phenotypic heterogeneity of FND and the diagnostic challenges it presents, emphasizing the role of neuroimaging in understanding its complex neural mechanisms and predicting treatment response. The paper underscores the importance of a nuanced understanding of FND in guiding clinical practice and future research. With advancements in neuroimaging techniques and growing recognition of FND's multifaceted nature, the paper suggests a promising trajectory toward more effective, personalized treatment strategies and a better overall understanding of the disorder. FND is estimated to affect at least 5% to 10% of new neurological consultations, ranking as the second most common reason for visiting a neurologist after headache. Recent studies have revealed varying prevalence rates across different populations, highlighting the disorder's significant burden and diversity. FND is associated with various biological, psychological, and social factors, including pre-existing psychiatric disorders, other somatic conditions, and lower socioeconomic status. The etiology of FND is multifactorial, involving neurobiological, psychological, and environmental factors. Personality traits, such as neuroticism and lower openness, have been linked to FND, although these traits are not universally present in all patients. The pathophysiology of FND involves complex interactions across multiple neural networks, including the limbic, salience, self-agency, multimodal integration, attentional, and sensorimotor circuits. Neuroimaging studies have revealed alterations in these networks, suggesting a multi-network brain disorder. FND's symptoms can vary in severity, progression, and treatment response, necessitating a personalized approach to diagnosis and treatment. The distinction between FND and deliberate symptom fabrication (feigning or malingering) is critical for proper diagnosis and treatment. Neuroimaging has provided evidence of distinctive neural function in FND compared to individuals feigning similar symptoms, supporting FND as a neurologically based disorder. The integration of neuroimaging findings with clinical and epidemiological data is essential for understanding and treating FND. The complexity of FND's pathophysiology and the need for a multidisciplinary approach highlight the importance of continued research and collaboration in improving diagnosis and treatment strategies.Functional neurological disorder (FND), previously known as conversion disorder, is a complex condition characterized by neurological symptoms without an identifiable organic cause. These symptoms, which can include motor, sensory, or cognitive disturbances, are not intentionally produced and vary in severity. Diagnosis relies on clinical evaluation and the exclusion of other medical or psychiatric conditions. Treatment typically involves a multidisciplinary approach addressing both neurological symptoms and underlying psychological factors through medical management, psychotherapy, and supportive interventions. Recent advances in neuroimaging and research into FND's epidemiology, pathophysiology, and clinical presentation have provided new insights into the disorder. This review highlights the phenotypic heterogeneity of FND and the diagnostic challenges it presents, emphasizing the role of neuroimaging in understanding its complex neural mechanisms and predicting treatment response. The paper underscores the importance of a nuanced understanding of FND in guiding clinical practice and future research. With advancements in neuroimaging techniques and growing recognition of FND's multifaceted nature, the paper suggests a promising trajectory toward more effective, personalized treatment strategies and a better overall understanding of the disorder. FND is estimated to affect at least 5% to 10% of new neurological consultations, ranking as the second most common reason for visiting a neurologist after headache. Recent studies have revealed varying prevalence rates across different populations, highlighting the disorder's significant burden and diversity. FND is associated with various biological, psychological, and social factors, including pre-existing psychiatric disorders, other somatic conditions, and lower socioeconomic status. The etiology of FND is multifactorial, involving neurobiological, psychological, and environmental factors. Personality traits, such as neuroticism and lower openness, have been linked to FND, although these traits are not universally present in all patients. The pathophysiology of FND involves complex interactions across multiple neural networks, including the limbic, salience, self-agency, multimodal integration, attentional, and sensorimotor circuits. Neuroimaging studies have revealed alterations in these networks, suggesting a multi-network brain disorder. FND's symptoms can vary in severity, progression, and treatment response, necessitating a personalized approach to diagnosis and treatment. The distinction between FND and deliberate symptom fabrication (feigning or malingering) is critical for proper diagnosis and treatment. Neuroimaging has provided evidence of distinctive neural function in FND compared to individuals feigning similar symptoms, supporting FND as a neurologically based disorder. The integration of neuroimaging findings with clinical and epidemiological data is essential for understanding and treating FND. The complexity of FND's pathophysiology and the need for a multidisciplinary approach highlight the importance of continued research and collaboration in improving diagnosis and treatment strategies.