The Essential Run-D.M.C. is no small consolation for being unable to obtain all of the group's albums. Indeed, something of this scope -- following many single-disc overviews -- has been necessary for a long time, as Run-D.M.C.'s catalog is too deep to be sufficiently summed with one disc. Across two discs, there's every necessary Run-D.M.C. single and album cut, including the classics "Hard Times," "It's Like That," "Rock Box," "King of Rock," "It's Tricky," and "Down with the King." The set pays tribute to DJ Jam Master Jay by closing disc one with "Pause" (featuring the man's first appearance as an MC) and by closing disc two with a seven-minute mix of "Jam Master Jammin'" (which went unreleased until the 2005 reissue of King of Rock). Bill Adler, pioneering hip-hop publicist and author of Tougher Than Leather: The Rise of Run-D.M.C., provides quotable-crammed liner notes.