Leo's contributed to the number one selling albums A Grand Don't Come For Free and The Hardest Way To Make An Easy Living which culminated in a BRIT Awards appearance in 2006 alongside Mike Skinner. During his time in The Streets, Leo performed all around the globe, as well as headlining V Festival and Reading Festival. Skinner gave him the nickname of "Leo the Lion". Leo has sung with many British acts, most notably rap duo The Mitchell Brothers and Kano.
Leo left The Streets so he could join Love Island and has collaborated with Kano on the single "Nite Nite" which became one of the most played videos on MTV that year. In 2011 Leo released two singles, "Rave To Coldplay" and "Am I The Only One", both of which are available for free download on his website.