The cultivation of loving-kindness (mettā bhāvanā) is a popular form of meditation in Buddhism. In the Theravadin Buddhist tradition, this practice begins with the meditator cultivating loving-kindness towards themselves, then one’s loved ones, friends, teachers, strangers, enemies, and finally towards all sentient beings. In the Tibetan Buddhist tradition, this practice is associated with tonglen, whereby one breathes out (“sends”) happiness and breathes in (“receives”) suffering.