by Richie Unterberger 15 tracks covering the pioneering blues-rock guitarist's '60s work, which was by far his best and most influential. Bloomfield worked with a bunch of bands during the decade, and the compilation flits rather hurriedly from his contributions to the Paul Butterfield Blues Band and Electric Flag, to his collaborations with Al Kooper, as well as some late-'60s solo tracks (none of his groundbreaking mid-'60s work with Dylan is here). Collectors will be interested in the first five songs, which date from previously unreleased sessions produced by John Hammond in late 1964 and early 1965. Featuring Charlie Musselwhite on harmonica, this pre-Butterfield Blues Band outfit plays convincingly, but the material is standard-issue, and Bloomfield's vocals are thin and weak (they didn't improve much over time). As befits Bloomfield's considerable but erratic talent, this is an interesting but erratic compilation; seek out the first two Paul Butterfield albums for a more cohesive showcase of his skills.