What were the Los Angeles-based 'Wrecking Crew' best known for in the 1960s and 1970s?

The 'Wrecking Crew' was a loose collective of session musicians based in Los Angeles whose services were employed for thousands of studio recordings in the 1960s and 1970s, including several hundred Top 40 hits. The musicians were not publicly recognized in their era, but were viewed with reverence by industry insiders. They are now considered one of the most successful and prolific session recording units in music history.

Most of the players associated with the 'Wrecking Crew' had formal backgrounds in jazz or classical music. The group had no official name in its active years, and it remains a subject of contention whether or not they were referred to as "the Wrecking Crew" at the time.

The unit coalesced in the early 1960s as the de facto house band for Phil Spector and helped realize his 'Wall of Sound' production style. They subsequently became the most requested session musicians in Los Angeles, playing behind many popular recording artists including 'Jan and Dean', 'Sonny & Cher', the 'Mamas and the Papas', the '5th Dimension', Frank Sinatra, and Nancy Sinatra. The musicians were sometimes used as "ghost players" on recordings credited to rock groups, such as the Byrds' debut rendition of Bob Dylan's "Mr. Tambourine Man" (1965), the first two albums by the 'Monkees', and the Beach Boys' 1966 album 'Pet Sounds'.