Yoga nidra (literally 'sleep of the yogi') is a meditation practice from the non-dual Tantric tradition that induces physical, mental and emotional relaxation while remaining awake and alert, offering an experience of deep rest and meditative inquiry designed to facilitate recognition of one's essential nature.  

iRest Yoga Nidra is a modern version of this ancient practice as developed by Richard Miller, PhD.  This guided body centered, meditative technique is practiced while resting comfortably, either lying down or seated.  Traditionally offered in yoga studios and meditation centres, iRest Yoga Nidra is increasingly found in healthcare settings as well as being offered in homeless shelters, veteran settings and schools.   It has been used as a tool to reduce stress, overcome insomnia, anxiety, depression, resolve trauma, and personal problems.