From Foos in the monsoon, to the legions of Eminem and Deadmau5 devotees, plenty of action went down at Lollapalooza 2011. A small slice of it, however, happened behind the scenes, out of sight from festival-goers.
Backstage in the Billboard Tent, artists mixed and mingled, strapped on acoustic guitars, and brought their A-game in stripped-down performance sessions. Scroll through our video player below to watch sets from Karmin and Skylar Grey (who tackled Dre, Em and Skylar's "I Need a Doctor" together, impromptu-style), the Joy Formidable, Lissie, Grouplove, and Deluka. And be sure to check out our backstage portrait gallery for more behind the scenes action at Lolla.
Watch Our Video Interviews From Lollapalooza 2011: