NKOTBSB is a compilation album by American boy bands New Kids on the Block and Backstreet Boys. Released on May 24, 2011, the album features five hits from each group, two new joint recordings "All in My Head" and "Don't Turn Out the Lights" and mash up. The album debuted at number seven in the US, selling 40,000 in the first week of its release.

Both bands first performed together at the Radio City Music Hall in the summer of 2010, and a joint tour was announced later that year. In March 2011, fans were encouraged to vote online for their favourite tracks from the separate groups; choices that would influence the tracklist for their joint compilation album.