Mindfulness
A way of being in which someone cultivates an attitude of ongoing, non-judgmental, patient awareness of the present moment. It is not an active exercise so much as an ability to observe one's own thoughts, desires and feelings objectively, separating awareness from thinking by observing the thinking itself.
The formal practice of mindfulness, through activities such as breathing exercises, is an effective way to strengthen one's ability to be more consistently and effectively mindful.