Richter talked with American neuroscientist David Eagleman while working on the album's piece to learn about how the brain functions during sleep.

"[12] In the album's credits, Richter describes Sleep as an eight-hour lullaby that is meant to be listened to at night.

[10] Sleep was performed in its entirety from midnight to 8:00 AM at the Wellcome Collection in 2015 as the climax of the BBC Radio 3 "Science and Music" weekend.

[12] The album was also performed at the Philharmonie de Paris in 2017,[19] and outdoors in Grand Park, Los Angeles in 2018.

The Los Angeles performances had 560 beds and were timed so the final movement, "Dream 0 (till break of day)" would occur at dawn.

Typing while the fizz of ‘Never Fade Into Nothingness’ plays makes transforms Word documents in an epic dance of black pixels on white light, binary marks scratching into a too-bright glassy reflection.

Walking while the echo-drenched monastic vocals of ‘Non-Eternal’ exposes that the world we occupy is haunted is exhilarating and avoiding awkward work colleagues as ‘If You Came This Way’ patters out its motif, that dangles held violin notes over electronic burbles, is to experience the sound of solace itself.

"[25] Grayson Haver Currin of Pitchfork Media gave the album a positive review, stating, "At its best, Sleep feels like compositionally rigorous new age music.

[29] All tracks are written by Max RichterRough Trade Shops Special Edition CD2 ‡ Sales+streaming figures based on certification alone.