Within the Theravāda tradition, mindfulness (sati) is understood as a lucid, non-forgetful awareness that keeps the mind steadily with its chosen object and guards against unwholesome states. It is framed as right mindfulness (sammā‑sati) within the Noble Eightfold Path and as the first of the seven factors of awakening, providing the clarity that allows investigation, energy, joy, tranquility, concentration, and equanimity to arise. Scripturally, it is given systematic expression in the Satipaṭṭhāna and Mahāsatipaṭṭhāna Suttas, which outline the four establishments of mindfulness: contemplation of body, feelings, mind, and phenomena. These domains include practices such as mindfulness of breathing, awareness of postures and activities, observation of pleasant, painful, and neutral feelings, recognition of mental states as wholesome or unwholesome, and contemplation of hindrances, aggregates, sense bases, awakening factors, and the Four Noble Truths.

In lived practice, sati is cultivated through both samatha (tranquility) and vipassanā (insight) meditation. Mindfulness of breathing (ānāpānasati), as taught for example in the Ānāpānasati Sutta, serves as a foundational exercise that calms and stabilizes attention, and when fully developed is said to fulfill the four establishments of mindfulness and lead toward awakening. On this basis, mindfulness is then applied to observe the arising and passing of bodily and mental phenomena, revealing their impermanent, unsatisfactory, and selfless nature. Commentarial Theravāda often presents an integration of samatha and vipassanā, where mindfulness first supports concentration, sometimes deepening into jhāna, and then serves as the lens for insight into the three characteristics. Alongside this, some modern Theravāda approaches emphasize continuous, moment-to-moment mindfulness—sometimes called “dry insight”—where sustained observation itself is regarded as sufficient to sharpen insight without prior attainment of deep absorptions.

Monastic life provides a structured environment in which mindfulness is woven into almost every activity. Formal meditation periods focus on breath, body, or other satipaṭṭhāna objects, while the Vinaya’s detailed rules foster careful awareness of bodily actions, speech, and thought. Monastics are trained in sati‑sampajañña, mindfulness joined with clear comprehension, so that walking, eating, speaking, cleaning, and going on almsround all become fields for contemplative attention. This vigilant awareness functions protectively, guarding the sense doors and allowing the early detection and abandonment of greed, hatred, and delusion as they arise. In this way, mindfulness not only supports concentration and insight but also safeguards ethical conduct, keeping the precepts intact by catching unwholesome impulses before they manifest in action.

For lay practitioners, mindfulness is taught both in formal and informal modes. Formal training often begins with mindfulness of breathing to steady the mind, then extends into insight practice that observes body and mind as conditioned processes marked by impermanence, unsatisfactoriness, and non-self. Retreats and observance days at monasteries or meditation centers provide intensive opportunities to cultivate continuous mindfulness, but the practice is also encouraged at home and in ordinary routines. Everyday activities such as walking, standing, sitting, lying down, eating, working, and interacting with others are treated as occasions to sustain present-moment awareness and to notice intentions and reactions. When cultivated in this comprehensive way—on the cushion and in the midst of daily life—sati gradually weakens clinging and the defilements, and opens the way to the direct realization of nibbāna through experiential insight rather than mere belief.