What sati actually names
The Pāli sati derives from the verbal root sar-, to remember. The original sense is closer to keeping in mind than to the bare attention the contemporary English mindfulness often connotes. Sati is the faculty by which the practitioner does not lose track of what is happening — the breath, the body's posture, the felt quality of an arising emotion, the doctrinal frame within which all of these are being investigated. Bare attention is part of it; remembering the frame in which the attention is held is the other half. The Pāli commentators describe sati's characteristic quality as apilāpana — not floating away — a buoyancy of attention rather than a clamp on it.
Where it sits in the Buddhist analysis
Sati is the seventh factor of the Eightfold Path (sammā-sati, right mindfulness), one of the five spiritual faculties (indriya), and one of the seven factors of awakening (bojjhaṅga). The Satipaṭṭhāna Sutta — Foundations of Mindfulness — is the canonical instruction text, describing four domains in which sati is to be applied: body (kāya), feelings (vedanā), mind-states (citta), and dhammas (the doctrinal categories of experience analysed under various Buddhist schemes). It is the operative quality of vipassanā practice and the precondition for the insight into impermanence, dukkha and anattā that the path is structured around. The Visuddhimagga — Buddhaghosa's fifth-century compendium of Theravāda practice — treats sati as both the gate through which the practitioner enters every other stage and the guard that keeps the path from sliding into either dullness or agitation.
How it shows up in practice
Tara Brach's guided practice names sati only obliquely but the cadence is unmistakable: the practitioner is asked to notice what is here, to allow it, and to keep remembering — across the inevitable wandering — what the noticing is for. The Plum Village teachings train sati explicitly through bell sounds, eating practice and slow walking meditation, building a habit of returning that does not depend on a posture. Thich Nhat Hanh's teaching on emptiness, signlessness and aimlessness operates downstream of sati: the seeing it describes is what stabilised sati makes possible. Jon Kabat-Zinn's MBSR curriculum is the secularised clinical descendant — the body scan, the sitting practice, the everyday mindfulness exercises are each particular trainings of sati under a different name.
The translation problem
Translating sati as mindfulness — a choice made by the British Pāli scholar T. W. Rhys Davids in 1881 and never seriously displaced — was useful in 1881 and is misleading now. The English word has been thinned across a century of secular adoption, and *mindfulness* in current clinical-corporate usage typically names only the bare attention half of what sati actually is. The doctrinal half — the remembering of the frame — was the part the Buddhist path treated as load-bearing. Whether the bracketing of that frame in the clinical adaptations preserves the practice's transformative force is the central live debate of contemporary contemplative-science scholarship. Defenders argue that the practice is robust enough to do its work without doctrinal scaffolding; critics argue that sati without the path of which it is one factor is a stress-reduction tool, not a path.
What it isn't
Sati is not concentration — that is samādhi, with which sati is paired but not identical. It is not effortful gripping of attention; the buoyancy described in the commentaries is precisely the opposite of the clamped quality novices sometimes mistake for the practice. And it is not, in the classical analysis, ethically neutral: sammā-sati (right mindfulness) is differentiated from micchā-sati (wrong mindfulness) precisely because attention can be turned to ends that deepen craving as readily as to ends that loosen it. A skilled sniper has sati of a sort. The path-context — what the attention is for, the wider Eightfold Path in which it sits — is part of the definition the Buddha intended, and the part the popularisations most often drop.
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