Once Again was the second album released by Barclay James Harvest, in early 1971. It is generally regarded as one of their strongest efforts, featuring powerful, epic tracks such as "Song For Dying", "She Said", and "Mocking Bird", one of their best known songs. As was the case with their other early albums, it was recorded with a full orchestra.
On the track "Galadriel", Lees played John Lennon's Epiphone Casino guitar, an event later recounted in a song on the band's 1990 album Welcome To The Show titled "John Lennon's Guitar".
In an interview with Songfacts, Keith Damone (official biographer of Barclay James Harvest with his wife Monika) said John Lees wrote "Mocking Bird" back in 1968 while he was living with the parents of his future wife, Olwen. The song is based on a musical phrase from "Pools Of Blue", which he wrote around the same time.
In the Q & Mojo Classic Special Edition ‘’Pink Floyd & The Story of Prog Rock’’, the album came #39 in its list of "40 Cosmic Rock Albums".