What sati actually meant
Sati in the early Buddhist suttas is one of the seven factors of awakening — the faculty of remembering to be present, of recollecting the object of meditation, of catching the mind when it wanders. It is not a mood; it is a trainable cognitive function. The Buddha treats sati as a precondition for the deeper insight (paññā) practices, not as the goal itself. The full path includes ethics, concentration and wisdom; mindfulness is one cultivation within that path.
MBSR and the secular extension
Jon Kabat-Zinn founded the Mindfulness-Based Stress Reduction programme at the University of Massachusetts Medical School in 1979, deliberately stripping the religious and metaphysical apparatus from the underlying Vipassanā practice in order to make it accessible inside a hospital. The clinical effects (on chronic pain, anxiety, depression relapse) have been extensively replicated. The cost of the secularisation — whether removing the ethical and wisdom limbs leaves a partial practice prone to misuse — is a real ongoing debate inside the contemplative-research community.
What gets lost in popular use
Mindfulness in the corporate-wellness register often shrinks to focus or stress reduction — useful but partial. The serious practice includes the difficult emotions as fully as the pleasant ones; it includes the noticing of one's reactivity, including one's reactivity to the practice itself; it eventually opens onto the deeper insight practices (impermanence, suffering, non-self) that the secular framing tends to skip. Reading Tara Brach or Jack Kornfield closes the gap considerably.
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