Bluegrass Student Union is the Louisville, Kentucky barbershop quartet who won the 1978 SPEBSQSA International competition. They distinguished themselves by performing at a high level of proficiency on stage and in the recording studio throughout their 33-year career, and by continually improving their art, even after winning their gold medals. They credit much of their success to their coaches, Mary Jo Hatton Thompson, Don Clause, Ron Riegler, Gene Stickler and Ed Weber, to their chorus Director, Jim Miller, and to their long-time arrangers, Ed Waesche and Walter Latzko.

Allen Hatton (tenor) Ken Hatton (lead) Dan Burgess (baritone) Rick Staab (bass). Allen Hatton later sang tenor with the original version of the Second Edition quartet to win the Cardinal District Quartet Championship for his second time. Ken Hatton later sang lead with the 2000 Cardinal District Champion SENSATIONS quartet, who earned semi-finalist status (20th place) in the 2001 International Quartet Competition. Ken also sang lead with The Exchange, semi-finalist (20th place) in the 2003 International Quartet Competition of SPEBSQSA, Inc.

The Bluegrass Student Union quartet was inducted into the Cardinal District Hall of Fame in 2005.

Awards
1978 - Barbershop Quartet Champions