When Jaco Pastorius’ solo debut appeared in 1976, a new standard in both jazz and the electric bass guitar was born. Many of the tracks on that eponymous album had their genesis two years earlier when a 22-year-old Pastorius and friends used after-hours time at Criteria Studios to work out songs and jam. Eventually, six of those session tracks were pulled to an acetate. Many of the songs would later find their way onto Jaco’s self-titled debut, but some remained unreleased until now. All tracks appear here in their full, unedited form for the first time.