This review article provides a summary of current data on the prevalence of anxiety and depression as comorbidities in COPD as well as the pathophysiological mechanisms thought to be responsible for their co-occurrence. The authors describe the impact of anxiety and depression on various aspects of COPD, including mortality, exacerbations and quality of life. Of particular interest to the PRAXIS community will be the finding that depression and anxiety increase the risk of hospitalization for COPD exacerbation and are also associated with longer hospital stay. Diagnosis and treatment of these in the COPD patient are also discussed, including the use of relaxation and cognitive behavioral therapies (CBT), self-management strategies, pharmacotherapy and pulmonary rehabilitation, which research has shown to improve depression and anxiety symptoms.