Peter Joseph Andrew Hammill is an English musician and recording artist. He was a founder member of the progressive rock band Van der Graaf Generator. Best known as a singer-songwriter, he also plays guitar and piano and produces his own recordings and occasionally those of other artists. In 2012, he was recognised with the Visionary award at the first Progressive Music Awards.

Progressive rock is a broad genre of rock music that primarily developed in the United Kingdom through the mid- to late 1960s, peaking in the early 1970s. Initially termed "progressive pop", the style was an emergence of psychedelic bands who abandoned standard pop traditions in favour of instrumentation and compositional techniques more frequently associated with jazz, folk, or classical music. Additional elements contributed to its "progressive" label: lyrics were more poetic, technology was harnessed for new sounds, music approached the condition of "art", and the studio, rather than the stage, became the focus of musical activity, which often involved creating music for listening rather than dancing.