All songs wrriten, arranged, performed, engineered, mixed and produced by Haco.
"Japanese singer Haco's career ranged from the indie rock band After Dinner in the early '80s to the avant-pop trio Hoahio, often incorporating unusual sound sources and experimental musicians along the way. Happiness Proof is essentially very much a rock album with both punk and Japanese power pop surfacing as overt influences. Haco has a soft, airy voice and her lyrics (sung in both English and Japanese) are inflected with an intelligent sense of whimsy as she sings of the dreamier aspects of modern life. "Like bubbles in carbonated soda/I'm fighting against gravity" is a line in a plaint that might sound corny in the manner of the tritest rock anthems were it not for both her conviction in delivery and the percolation of electronic glitches and other ephemera. This sense of adventure and the relaxed, comfortable usage of otherwise avant-garde techniques make for an album far more enjoyable than standard pop fare. Recommended for those who like their light pop songs with a decided twist."-- Brian Olewnick, All Music Guide