Bryan, who served as co-host of Sunday night's ACM Awards with Blake Shelton, also won the Award for Vocal Event of the Year with Jason Aldean and Eric Church for "The Only Way I Know" before the CBS telecast at the MGM Grand Garden Arena began.
Eric Church won the Album of the Year honor for "Chief."
Lambert won for the fourth consecutive year as Female Vocalist of the Year, while Aldean won Male Vocalist of the Year.
Lambert also took the prize for Single Record of the Year as artist and Song of the Year as artist and composer, for "Over You." She shared the Song of the Year trophy with her husband and co-composer Blake Shelton.
Little Big Town won the award for Vocal Group of the Year, as well as Video of the Year for "Tornado."
Thompson Square won Vocal Duo of the Year and Florida Georgia Line earned the accolade for New Artist of the Year.
The New Male Vocalist of the Year statuette went to Brantley Gilbert and Jana Kramer took home the ACM Award for New Female Vocalist of the Year.
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