The piece was first displayed at Ono's "Half-a-Wind" exhibition (also called "Yoko Plus Me"[1]) at the Lisson Gallery in West London in 1967.
Half-a-Room was shown at Ono's exhibition from 10 November 2007 to 4 February 2008 at the Centro Cultural Banco do Brasil in São Paulo .
Ono had been to see Lennon's friend Pete Shotton, who was working for The Beatles company Apple Corps, and had asked to borrow a few thousand pounds to fund the exhibition.
Lennon later described the exhibition as all "beautifully cut in half and painted white...That was our first public appearance, but I didn't even go and see the show, I was too uptight".
[1] Half-A-Room has been described by Ono as a response to her feeling at the time that "there was a half empty space in my life" as a result of the increasing estrangement of her and her second husband, Anthony Cox.
"[6] The emotional impact of the end of her relationship with Cox subsequently inspired Ono to make her piece Ceiling Painting/Yes Painting.