"The Pirates of Penzance; or, The Slave of Duty" is a comic musical opera written by Arthur Sullivan and W. S. Gilbert in 1879. Gilbert and Sullivan were a Victorian-era theatrical partnership of the librettist W. S. Gilbert (1836-1911) and the composer Arthur Sullivan (1842-1900). Together they collaborated on fourteen comic operas between 1871 and 1896 which are still performed and loved today. Among their most famous works are ''H.M.S. Pinafore'', ''The Pirates of Penzance'' and ''The Mikado''. Classic Musicals Collection constitutes an extensive library of the most well-known and universally-enjoyed musicals and operas ever composed, reproduced from authoritative editions for the enjoyment of musicians and music students the world over.