Anxiety disorders, including panic disorder, generalized anxiety disorder, social anxiety disorder, specific phobias, and separation anxiety disorder, are the most prevalent mental health conditions, affecting up to 33.7% of the population during their lifetime. These disorders are associated with significant healthcare costs and a high burden of disease. Despite this, there is substantial underrecognition and undertreatment of these disorders, with no evidence of changes in prevalence rates over the past years. Cross-cultural comparisons show highly variable prevalence rates, which are more likely due to methodological differences than cultural influences. Anxiety disorders follow a chronic course, with a natural decrease in prevalence with age. They are highly comorbid with other anxiety disorders and mental health conditions. Epidemiological studies using large community surveys and clinical settings provide valuable insights into the prevalence, diagnosis, and treatment of anxiety disorders. However, challenges exist in accurately diagnosing and treating these disorders, particularly in outpatient and primary care settings. The economic burden of anxiety disorders is substantial, with costs exceeding 41 billion Euros in the European Union in 2004. Despite effective treatments, many affected individuals do not seek or receive appropriate care. Cross-cultural differences in prevalence rates are likely due to methodological variations rather than cultural factors. High comorbidity among anxiety disorders and with other mental health conditions further complicates their management. Epidemiological research plays a crucial role in developing treatment and prevention strategies and understanding the etiology of these disorders.Anxiety disorders, including panic disorder, generalized anxiety disorder, social anxiety disorder, specific phobias, and separation anxiety disorder, are the most prevalent mental health conditions, affecting up to 33.7% of the population during their lifetime. These disorders are associated with significant healthcare costs and a high burden of disease. Despite this, there is substantial underrecognition and undertreatment of these disorders, with no evidence of changes in prevalence rates over the past years. Cross-cultural comparisons show highly variable prevalence rates, which are more likely due to methodological differences than cultural influences. Anxiety disorders follow a chronic course, with a natural decrease in prevalence with age. They are highly comorbid with other anxiety disorders and mental health conditions. Epidemiological studies using large community surveys and clinical settings provide valuable insights into the prevalence, diagnosis, and treatment of anxiety disorders. However, challenges exist in accurately diagnosing and treating these disorders, particularly in outpatient and primary care settings. The economic burden of anxiety disorders is substantial, with costs exceeding 41 billion Euros in the European Union in 2004. Despite effective treatments, many affected individuals do not seek or receive appropriate care. Cross-cultural differences in prevalence rates are likely due to methodological variations rather than cultural factors. High comorbidity among anxiety disorders and with other mental health conditions further complicates their management. Epidemiological research plays a crucial role in developing treatment and prevention strategies and understanding the etiology of these disorders.