This book is by no means an exhaustive, complete study of human anatomy or the vast science of yoga. No single book possibly could be. Both fields contain a potentially infinite number of details, both macro- and microscopic—all of which are endlessly fascinating and potentially useful in certain contexts. My intention is to present what I consider to be the key details of anatomy that are of the most value and use to people who are involved in yoga, whether as students or teachers. To accomplish this, a particular context, or view, is necessary. This view will help sort out the important details from the vast sea of information available. Furthermore, such a view will help to assemble these details into an integrated view of our existence as “indivisible entities of matter and consciousness.”1 The view of yoga used in this book is based on the structure and function of the human body. Because yoga practice emphasizes the relationship of the breath and the spine, I will pay particular attention to those systems. By viewing all the other body structures in light of their relationship to the breath and spine, yoga becomes the integrating principle for the study of anatomy. Additionally, for yoga practitioners, anatomical awareness is a powerful tool for keeping our bodies safe and our minds grounded in reality. The reason for this mutually illuminating relationship between yoga and anatomy is simple: The deepest principles of yoga are based on a subtle and profound appreciation of how the human system is constructed. The subject of the study of yoga is the Self, and the Self is dwelling in a physical body.