Vol. 4 in JSP's thorough and affordable series of four-CD sets devoted to the complete works of Fats Waller contains all of his studio recordings made in New York, Chicago, and Hollywood between September 9, 1936, and April 12, 1938. This segment of Waller's astonishingly prolific career found him leading so many inspired and artistically rewarding sessions that Vol. 4 is recommended as heartily as was the previous installation. There are 102 tracks in total, including eight alternate takes sewn onto the end of the fourth disc along with a rare alternate realization of "Big Business, Pts. 1-2," an original cast recording from the revue Hot Chocolates that features a theater ensemble led by comedians Billy Higgins and Eddie Green with bluesy instrumental accompaniments by pianist Thomas Waller. This classic if Jim Crow-infused example of early-20th century Negro vaudeville provides crucial context for the showbiz environment within which Waller developed his skills and ultimately prevailed as one of the nation's most popular entertainers. During the year 1937 Fats Waller & His Rhythm recorded some of their all-time greatest instrumentals, including "Boo Hoo," "Blue Turning Grey Over You," and the famous four-minute version of "Honeysuckle Rose." Eight of the vocal tracks from this period are followed by instrumental flip sides that allow for more solos and creative interaction between the players. This formula worked especially well on the bluesy "San Anton'" and the ebullient "Swingin' Them Jingle Bells." In addition to nine examples of what he sounded like at the helm of a 13-piece big band (Disc D tracks seven through 15), Waller is mostly heard with his core Rhythm band (trumpeter Herman Autrey, reedman Eugene Sedric, guitarist Albert Casey, bassist Charles Turner or Cedric Wallace, and drummer Wilmore Slick Jones). He also performs as a solo pianist (Disc B tracks 23-26); in a jam session at Victor with trumpeter Bunny Berigan, trombonist Tommy Dorsey, guitarist Dick McDonough, and drummer George Wettling (Disc B tracks 5 and 6); and with a short-lived West Coast version of his Rhythm, whose recordings are most memorable for the steel guitar work of Ceele Burke (Disc C tracks 16-23). This group's renderings of "Georgia on my Mind" and "On the Sunny Side of the Street" were non-commercial audition recordings for warm-voiced singer Peggy Dade, and would not become available to the public until decades later during the first truly comprehensive posthumous Fats Waller LP reissue projects.