Following the departure of Eric Clapton, Peter Green (b. 1946) joined John Mayall's Bluesbreakers in July 1966. He is featured on the album A Hard Road (1967), recorded in October 1966, on which he displays an uncommon sensitivity and melodiousness. He approaches Freddie King's "The Stumble" with his highly original touch and sound, and idiosyncratic timing. His composition "The Supernatural" looks forward to the arrangements he was later to develop with his own group, Peter Green's Fleetwood Mac. After A Hard Road, one of the highlights of his career is "Greeny," the instrumental on which he displays astonishing tonal variety and delicate fragility as he reaches for expressive phrases. Peter Green's Fleetwood Mac, formed in 1967, consisted of ex-Bluesbreakers Mick Fleetwood on drums and John McVie (b. 1945) on bass, with Jeremy Spencer (b. 1948) on guitar. They started recording in the autumn of 1967, working alongside American blues artists. Adding a third guitarist, Danny Kirwan (b. 1950), in 1968, the group went on to develop their finest material around Green's compositions and arrangements.

With the supportive interplay of the other guitarists, Green's vocals and guitar solos are showcased on "Black Magic Woman" (1968). Beginning with a shimmering three-note chord played with vibrato, this composition features a tasteful and emotional melodic solo using expressive string bending and arpeggio motifs His understated melodic sensitivity can also bi heard on traditional material such as Little Willie John's "Need Your Love So Bad," in which short guitar phrases play a counterpart to Green's heartfelt vocal.

Green often used reverb to position music; elements and set moods. On the instrumental "Albatross" (1968), gently strummed chords, high-register lines, and mellifluous slide are mixed to produce a dreamlike instrumental with underlying mesmeric bass and cymbals.

In one of Green's most personal songs, "Man Of The World" (1969), the guitar parts are carefully layered and arranged. It opens with folk-style fingerpicking on steel-string guitar chords with nylon-string fills, and break into rhythm with electric guitar and additional background elements.

Green finally left the group he founded in 1971. His 1970 solo album, The End of the Road, has an appropriate title for an outstanding artist who was unable fully to concentrate on music again for some time.