Almost a half-century after Yayoi Kusama debuted her landmark installation Infinity Mirror RoomPhalli's Field (1965) in New York, the work remains challenging and unclassifiable. Shifting between the Pop-like and the Surreal, the Minimal and the metaphorical, the figurative and the abstract, the psychotic and the erotic, with references to free love and psychedelia, it seemed to embody all that the 1960s was about, while at the same time denying the prevailing aesthetics of its time. The installation itself was a room lined with mirrored panels and carpeted with several hundred brightly polka-dotted soft fabric protrusions into which the visitor was completely absorbed. Kusama simply called it a sublime, miraculous field of phalluses. A precursor of performance-based feminist art practice, media pranksterism, and Occupy movements, Kusama (born in 1929) was once as well known as her admirersAndy Warhol, Donald Judd, and Joseph Cornell. In this first monograph on an epoch-defining work, Jo Applin looks at the installation in detail and places it in the context of subsequent art practice and theory as well as Kusama's own (as she called it) obsessional art.