This is volume five in the Classics Mildred Bailey chronology. It contains all of the Vocalion records she made between January 18 and June 14, 1939. For all of her concessions to mainstream pop culture, Mildred Bailey was a blues-inflected jazz singer with traditional roots reaching back into the early '20s. Each of the ensembles featured on this particular compilation are decidedly hipper than most of her previous backup bands. Bailey's March 16, 1939 session with pianist Mary Lou Williams, guitarist Floyd Smith, bassist John Williams and drummer Eddie Dougherty resulted in a series of fine and soulful renderings of old time melodies like the "Arkansas Blues," "Gulf Coast Blues," "You Don't Know My Mind Blues" and Russ Columbo's "Prisoner of Love." Sixteen of this compilation's 22 tracks feature the John Kirby Sextet. This brilliant and creatively concise group had a frontline of trumpeter Charlie Shavers, clarinetist Buster Bailey and alto saxophonist Russell Procope; its well-oiled rhythm section contained pianist Billy Kyle, bassist John Kirby and drummer O'Neill Spencer. This little band was capable of handling material from the jazz, pop and European classical traditions; the Bailey/Kirby magic is most evident on Cole Porter's "Begin the Beguine," Ziggy Elman's "And the Angels Sing," Lovie Austin and Alberta Hunter's "Down Hearted Blues" and the "Tit Willow" aria from Gilbert & Sullivan's Mikado. On most of the Kirby sides, xylophonist Red Norvo can be heard obviously enjoying the opportunity to collaborate with exceptionally gifted improvisers. Premonitions of things to come! Norvo dissolved his big band in June 1939, not long after the recording of "I'm Forever Blowing Bubbles," and began working with smaller, more modern-sounding ensembles. While Red Norvo would become an integral participant in the bop revolution of the '40s and '50s, Mildred Bailey's career gradually decelerated during the '40s, particularly after her health began to deteriorate. The records she cut during the first half of 1939 add up to some of the best music she ever made. For that reason, this particular installment in Mildred Bailey's Classics chronology is most highly recommended.