Overcoming the burden of depression remains one of the most significant challenges in managing bipolar disorder. Compared to mania, depressive episodes in bipolar disorder are more frequent and considerably longer in length, with individuals spending roughly one-third to one-half of their lives suffering from depressive symptoms. Most of the difficulties with functioning at work, home, or school are due to depressive episodes, and most suicides occur in the context of a depressive (vs. manic) episode. Medication treatment of bipolar depression is not straightforward. Some individuals have a poor response to mood stabilizing medications, experience switches into mania as a result of antidepressant use, and have trouble taking their medications as prescribed. Thus, there remains a need for treatments that individuals with bipolar depression can use in addition to medication. As a practice that incorporates elements of physical exercise, controlled breathing, and meditation, hatha yoga has frequently been recommended as a way to manage bipolar disorder symptoms. There are numerous reasons why hatha yoga may be helpful for bipolar depression. First, there is some evidence that hatha yoga is useful for unipolar depression. Second, it is possible that yoga may help individuals with bipolar disorder regulate their daily routines, decrease negative depressive thoughts, and have a positive impact on biological mechanisms related to bipolar disorder. Yet to our knowledge, there have been no published studies on the benefits - and potential risks - of the practice of yoga in bipolar disorder. The primary aim of the proposed pilot study is to develop a 10 week yoga program specifically tailored to bipolar depression. We will develop an instructor manual for teaching classes and a scale for measuring instructor adherence to the manual. We will evaluate the feasibility, acceptability to patients, and safety of this program in a 10 week pilot randomized controlled trial (RCT). In this trial, we will enroll 36 participants with bipolar I/II depression, and randomly assign them to either: 1) the yoga intervention, delivered as an adjunct to treatment as usual; or 2) treatment as usual enhanced with a publicly-available bipolar disorder self-help book (ETAU). In a preliminary fashion, we will examine whether the yoga classes (compared to ETAU) appear promising in terms of reduced symptom severity and improved quality of life.