This two-disc set, running as long as CDs allow, provides a comprehensive look at the second and final decade of the Supremes, the era after lead singer Diana Ross left, when sole original member Mary Wilson juggled personnel changes and struggled with Motown Records and the changing musical times to try to maintain the group's success. She did that with some degree of effectiveness, especially in the first few years. It's apparent that Motown did make some efforts to support the Supremes, providing Smokey Robinson and Stevie Wonder as at least occasional writer/producers, with their old hitmakers -- Brian Holland, Lamont Dozier, and Edward Holland Jr. -- even coming back in toward the end. The result was a batch of hits, including the R&B chart-topper "Stoned Love," through mid-1972. It is not clear why the group had no album releases in 1973 or 1974, and Wilson in her liner notes doesn't seem to know, either. But by the time they returned to recording in 1975, despite the efforts of the Holland brothers and a series of disco-styled recordings that scored in the dance clubs, the old momentum was lost, especially as the lineup changed, with lead singer Jean Terrell giving way to Scherrie Payne, and the Supremes disbanded in 1977. On the hits, select album tracks, and some revealing previously unreleased material, one can hear the group's development. Their versions of well-known songs by others -- Stephen Stills' "Love the One You're With," Joni Mitchell's "All I Want," Bread's "Make It With You," the Jackson 5's "Never Can Say Goodbye" -- are illuminating, and hits like "Up the Ladder to the Roof" and "Floy Joy" hold up well. The later editions of the Supremes may not rank with the Diana Ross-led '60s version, but this collection demonstrates that they had their own appeal.