Background: Consultation-liaison (C-L) psychiatry, informed by principles of psychosomatic medicine, is well-positioned to address the global impact of mental disorders through primary care C-L models. Objective/Method: The authors review the international burden of mental disorders, highlighting medical comorbidity, undertreatment, and the rationale for enhancing primary-care management. Results: C-L psychiatry fosters the skills required for global mental health work. The authors describe successful C-L models developed in a low-income country (Ethiopia) and an under-resourced region of a high-income country (Australia). Conclusion: C-L psychiatrists have the potential to marshal their unique skill-set to reduce the global burden of mental disorders.