Not much has been said about Duke Ellington's Reprise Records period, and even less that's enthusiastic, mostly owing to the fact that his output there ran between two extremes: dazzlingly inventive conceptual pieces juxtaposed with re-recordings of classic big-band material, and pop-jazz efforts built around covers of current popular songs. Amid that wildly divergent body of work, it's no surprise that the live material from The Great Paris Concert and Ellington's Greatest Hits eclipsed much of his Reprise studio work. Thus, this five-CD box is the first opportunity that most listeners will have had to assess the music properly. As with all Mosaic issues, it's in recording session order, and Disc One opens with Ellington's 1962 covers of classic big-band material. Disc Two is where things not only get interesting but downright spellbinding, containing the entirety of the Afro-Bossa Album -- this is some of the most beautiful, engaging, and forward-looking music of Ellington's 1960s output, and the varied rhythms and textures are coupled with some truly luscious playing. Disc Three is largely given over to the material off of Symphonic Ellington, mixed band and orchestra pieces dating from the period in which Ellington began writing concert music for orchestra. Disc Four is devoted to the Ellington '65 and Ellington '66 albums, renditions of current pop and rock & roll hits. Few of Ellington's serious fans have ever professed much love for his Mary Poppins album, the contents of which open Disc Five, but the material holds up quite well, mostly because the soloists are enjoying themselves. As usual with Mosaic, the annotation and sessionography material are thoroughly detailed.