It Only Happens Once is a romantic ballad written by Frankie Laine during his early career, before he achieved fame as one of the most popular vocalists of the late 1940s and 1950s. Laine composed the song during a formative period when he was working to establish himself in the music industry, and it stands as an example of his often-overlooked talent as a songwriter alongside his more celebrated work as a performer. The song explores the theme of a singular, irreplaceable emotional experience, fitting squarely within the 1940s popular ballad tradition. Among the earliest and most notable recordings is the version by the Nat King Cole Trio, reflecting the esteem in which Cole held the material -- the two artists maintained a close friendship throughout Cole's life. Laine himself recorded the song in 1947. While the composition did not reach the level of recognition enjoyed by Laine's signature vocal performances on songs like "Mule Train" or "Jezebel," it circulated among jazz and pop artists of the era. More recently, the tune appeared on The Jazz Soul of Frankie Laine, a retrospective project featuring new jazz arrangements of Laine's compositions by arranger Mark Masters with baritone saxophonist Gary Smulyan. It Only Happens Once remains a modest entry in the American popular songbook, valued by musicians drawn to the depth of the mid-century ballad repertoire.