Mundy was an English composer of sacred vocal music during one of the most dynamic eras in English music. Little is known of Mundy's life, but it is known that he served as a Gentleman of the Chapel under Queen Elizabeth and so enjoyed some renown during his lifetime. At least one writer praised him as the second greatest composer of the age, after William Byrd. Mundy's music exhibits a wide range of styles, from the older Latin antiphon tradition to the modern English verse anthem. Though his compositions are based on the current syllabic style of text setting, with restrained and tightly controlled counterpoint, Mundy often indulges in elaborate passage-work, especially at the end of a piece.
Mundy's output contains masterful pieces in several difficult genres. His magnificent votive antiphon "Vox patris caelestis" impressively crowns the grandiose antiphon tradition of the previous century of English music, and is perhaps the finest example in post-Reformation music. His English anthems are also masterly essays in that developing genre, and his verse anthems with organ accompaniment are among the earliest examples in what was to become the dominant style of English cathedral music. These divergent compositions – all of high quality – show Mundy to have been possessed of a unique combination of historical reflection and brilliant innovation, even if his name was forgotten shortly after his death.