Patients with major depressive disorder (MDD) often present with pain or other physical symptoms in addition to psychological symptoms. This finding has been replicated in studies across the globe, even though the prevalence of MDD varies greatly internationally. The greater the number of physical symptoms, the more likely the patient is to have a mood disorder, but the presence of pain or physical symptoms negatively impacts physicians' ability to recognize MDD. To improve the recognition of MDD and ensure that patients receive appropriate treatment, clinicians should perform a differential diagnosis that includes psychiatric disorders when patients present with chronic pain or other somatic symptoms.