This chapter provides a comprehensive overview of the conceptualization and presentation of breath in the major religious-philosophical traditions of ancient India. It firstly outlines the significance of breath in the earliest Indian records, drawing primarily from the Vedas and their commentarial textual sources, and then follows a survey of the central role of breath in ancient Indian yogic traditions, from the earliest records such as the Yogasūtra to later developments and new foci, which are reflected in a variety of contemporary, globalized yogic practices. The majority of the chapter is dedicated to presenting the conceptualization of breath in early Buddhism, with a focus on mindfulness of breathing. This section examines the explicit and implicit links between mindfulness and ethical praxis, both of which are embedded in the notion of nonself, as delineated within the early Buddhist soteriological model. It points out that contemporary applications of mindfulness, which have been disseminated worldwide in a range of diverse settings, have largely overlooked the ethical grounding of mindfulness, which is nevertheless centrally situated in Buddhist discourse. The chapter concludes by reflecting on how a critical awareness of the linkage between mindful breathing and ethics may serve as a corrective to current secular interpretations of mindfulness.