Bagatelle are an Irish rock band who first formed in August 1978. They are well known for their popular pop hits such as 'Second Violin', "Leeson Street Lady" and "Summer in Dublin", perhaps their best known and best loved song.

Formed in Bray, Co. Wicklow, Ireland, the band first started to get noticed around the 70's. Fellow Irish musician Bono has commented on the impact that Bagatelle had on U2 in the early days of their career, Larry Mullen, of the same band, once famously said that he used to call them "Baga-Money", in reference to their fame, and that he wished that his band could be as successful as them.