The Grammy Award for Best Country Duo/Group Performance is an award presented at the Grammy Awards, a ceremony that was established in 1958 and originally called the Gramophone Awards. It was first awarded in 2012, after a major overhaul of Grammy Award categories. The award combines the previous categories for Best Country Performance by a Duo or Group with Vocal, Best Country Collaboration with Vocals and Best Country Instrumental Performance (if the instrumental recording is performed by a duo or group). The restructuring of these categories was a result of the Recording Academy's wish to decrease the list of categories and awards.
According to the 54th Grammy Awards description guide it is designed for duo/group or collaborative (vocal or instrumental) country recordings and is limited to singles or tracks only.Wikipedia