This playful track originally appeared in Haim's 2012 Daytrotter session and featuring prominently in their live setlists, where it proved to be a favorite. When the sisters came to record the tune for their debut album they tried laying it down in a variety of different ways from raw Rock 'n' Roll to Electronica. "It's like the hardest math problem ever, " Este Haim told NME. "We want to get it right – we love that song." The cut was released as a single on September 23, 2013.
The song's music video finds the Haim sisters dumping their respective partners. The clip co-stars Jorma Taccone of the Lonely Island as one of their spurned boyfriends. Taccone also had a recurring role on HBO's Girls.
John Lennon's lead guitar work on Yoko Ono's "Walking On Thin Ice" proved to be his final creative act. It was upon their return home after completing laying down the track that Lennon was murdered by Mark David Chapman.
"Lean On" was originally sent by Major Lazer to both Rihanna and Nicki Minaj's camps as a slower reggae track. After both parties rejected the tune, Major Lazer recruited Danish singer MØ to supply vocals and recorded it themselves.