The goal of this research is to evaluate whether Tai Chi merits further investigation as a non-pharmacological therapy in the treatment of Major Depressive Disorder (MDD). Specifically, this waitlist-controlled study will gather preliminary data evaluating the effectiveness of Tai Chi training as treatment for patients with MDD or a history of MDD, including patients who continue to be depressed despite taking antidepressants and patients who choose not to take antidepressants due to fear of side effects and/or for personal reasons. To test this hypothesis the investigators will compare physical and psychological parameters of a control group and an intervention group, at baseline (Week 0), at the midpoint (Week 6), and at the end of 12 weeks of Tai Chi training.

When a first line treatment for depression fails, clinicians often choose to increase the dosage, or augment with a second agent, prior to considering switching agents altogether (Rosenbaum et al, 1995). Combination of an SSRI/SNRI with other agents such as tricyclic antidepressants (TCAs) or lithium are examples of popular strategies (Fava et al, 1994). In many instances, augmentation with multiple psychotropic agents may not be desirable, because of risk of side effects or drug-drug interactions.

In view of their benign adverse effect profiles, non-pharmacological interventions such as psychotherapy and mind-body intervention have been used to augment treatment for treatment resistant depressed patients. Preliminary studies have shown that meditation is beneficial for the treatment of depression (Smith et al., 2007; Sephton et al., 2007; Finucane and Mercer, 2006; Astin et al., 2003; Speca et al., 2000).

Tai Chi training consists of a sequence of slow, soft, and graceful movements derived from the martial arts. It is considered as a moving form of yoga and meditation combined. Tai Chi has been considered as one form of oriental healing arts, like acupuncture, which fosters the circulation of this 'chi' or energy within the body. By doing so, the health and vitality of the person are enhanced. Tai Chi, with its slow movement synchronized to the person's breathing, has been known to lead to a calm and tranquil mind when the person is focused on the precise execution of these exercises.

General Inclusion criteria

• Men and women between the ages of 18 and 65 years;
• Satisfy DSM-IV criteria for current Major Depressive Disorder (MDD), or have a history of MDD, prior to the initiation of Tai Chi treatment, as determined by the SCID interview;
• Have not had Tai Chi treatment training and have not started other forms of mind/body intervention in the past 3 months.

General Exclusion criteria

• Patients with primary diagnosis other than MDD and/or do not have a history of MDD;
• Conditions that may make it difficult to conclusively determine that depressive symptoms are the result of MDD or having a history of MDD and not some other condition, including any form of substance abuse or dependence within the last 6 months, relevant medical conditions that may be the medical basis of a depression including epilepsy, history of an abnormal EEG, severe head trauma, or stroke;
• Medical conditions that would preclude entry into a clinical trial, including serious uncontrolled medical conditions (e.g. poorly controlled diabetes, severe congestive heart failure), or other medical conditions that have not been stable for a minimum of 3 months);
• Confounding treatments, such as current ongoing treatment other than what is provided by South Cove for depression; plans to receive confounding treatments.