Over the course of the period covered here, 1991-2012, R. Kelly produced a varied and substantial back catalog -- one that can't be neatly summarized in two discs. Even if The Essential R. Kelly played it straight and included only his solo Top 20 R&B singles, it wouldn't be more representative. Since Kelly's work is so broad, ranging from traditional soul and adult contemporary to outlandish contemporary R&B, one would be better off assembling her/his own set of favorites on a track-by-track basis. This does provide an adequate sampling of Kelly's best work, including "She's Got That Vibe," "Bump N' Grind," "Ignition," "Step in the Name of Love," and "Feelin' Single." Its track list is significantly different compared to that of The World's Greatest, released in the U.K. in 2011, yet both sets are of roughly equal value.