To forge toward something greater is the idea behind the term progressive, and progressive rock has taken that definition and ran with it. "Beyond and Before: Progressive Rock Since the 1960s" follows the history of progressive music and its roots. Blending the emerging genre of rock and roll with its parental concepts, Paul Hegarty & Martin Halliwell do well in breaking down these roots and how it keeps marching forward, even as modern groups like Radiohead and the Mars Volta dare to push out something different than standard popular music fare. "Beyond and Before" is a fine study on the advancement of music, highly recommended.