His first steady work was in the territory band, the Ernie Williamson Orchestra, in the late nineteen thirties . During the Second World War stationed in Sacramento, California, , Cavanaugh was the replacement pianist for an Army trio called The Three Sergeants, and in that group made the acquaintance of Al Viola and Lloyd Pratt who would form a musical partnership after their military service was over.
By the mid forties, now based in Los Angeles, the small unit called The Page Cavanaugh Trio began to get club work in the Southern California area. They patterned their musical style after the King Cole Trio and developed a unique vocal sound which consisted of soft voiced unison singing. Soon they were garnering great reviews and spreading popularity. They began recording for small West Coast labels and soon found a few musical spots in motion pictures.