Interested in pursuing a career in the U.S., Lejeune performed his song on ABC’s The Joe Franklin Show. Later nicknamed ‘The French Boy’, Cashbox Magazine predicted that the Quebec artist was destined to an enormously successful career in the U.S. Lejeune went on to appear on more American variety shows, including The Jack Parr Show on NBC. The young performer made a strong impression on the American public, and received many interesting offers.

Following a bad experience with a sly, aggressive agent, Lejeune returned to Quebec where his popularity had kept growing and where he received a hero’s welcome. In 1959, Une promesse won the Best Canadian Composition Award as part of Montreal radio station CKAC’s Grand Prix du Disque. Following the success of the piece, Lejeune toured Quebec’s clubs and ‘boîtes à chansons’, and gave a triumphant performance at the Comédie Canadienne theatre with Jean Coutu in a programme of song and poetry. Lejeune continued to perform in the U.S. with well-known orchestras for audiences that wanted to hear more from ‘The French Boy’.

Une promesse remains to this day André Lejeune’s greatest hit in a career that produced some 30 top-charting songs and hundreds of original works.