Depression is the most common psychiatric disorder in coronary artery disease, and it can worsen cardiac outcomes. Also, cardiac disease predisposes patients to the development of depression. Assessment of depression is an important part of ongoing patient contacts. It can be easily done through the regular use of a self-report screening tool and the clinical interview. Treatment can consist of antidepressant use, psychotherapy and mindfulness-based group therapy. The antidepressants known as the selective serotonin reuptake inhibitors can generally be used safely in cardiac patients. They are a mainstay in the treatment of moderate to severe depression. Individual cognitive-behavioral therapy can treat milder forms of depression and can augment antidepressant use in more severe cases. Mindfulness-based group therapy can provide patients with additional means of handling distress while offering social contact and support, both of which are important in the treatment of depression. The use of consulting psychiatric services offers the cardiologist a collaborative team approach when treating patients with depressive illnesses.