On 20 September 1964 Charles Mingus played a set at the Monterey Jazz Festival that opened with a long Ellington tribute and built towards Meditations on Integration. His band with Jaki Byard, Dannie Richmond, John Handy, Charles McPherson and Lonnie Hillyer was expanded into a small orchestra for the closing piece, with Buddy Collette on flute and Red Callender on tuba among others. Mingus issued the recording himself on his own mail-order label Jazz Workshop, which is why the album was hard to find for decades afterwards. The music shows how he steered an ensemble live, with tempo shifts and collective passages that came out differently at every performance.

This edition is a 2LP on black vinyl, released for Record Store Day.