While at the University of Pittsburgh in 1982, Kantner became a referee at basketball games for churches.[5][6] Following her post-secondary education, Kantner started her engineering career as a pipe stress analysis consultant. She continued her engineering experience in the sales department for Westinghouse Electric Corporation during the early 1980s and worked in Asheville, North Carolina.[7] By the early 1990s, Kantner was working in Charlotte, North Carolina, in her sales position.[8] Kantner ended her engineering tenure in 1997, when she was hired as an NBA official.[4]
During 1992, she worked for the Big Ten Conference and five other conferences simultaneously.[8] In the mid-1990s, Kantner worked as a salesperson for Cutler-Hammer while working as a college basketball referee.[11] By 1997, Kantner was refereeing for eight conferences at the same time. These included the Pac-10 Conference and West Coast Conference.[12] Outside of college basketball, Kantner refereed in 1995 for the Summer Pro League.[13]
Kantner remained with the NBA until she was fired in 2002.[16] After leaving the NBA, she continued to work in the WNBA as the Director of Referee Development from 2002 to 2004 and was renamed Supervisor of Officials in 2004.[15] By 2019, Kantner had remained in her supervisory role with the WNBA for almost 15 years.[17] For the NCAA, Kantner has been a referee in over twenty Final Four rounds since 1992 and over ten championship games in women's basketball.[18][19]
Outside of the NCAA, Kantner has also worked as a referee for the Continental Basketball Association.[15] At individual events, Kantner was a referee during the National Sports Festival held in 1991.[20] During 1993, she was scheduled to work as a referee during the qualification of the U.S. Olympic Festival.[21] Kantner reffed a quarterfinal game during the women's basketball event at the 2000 Summer Olympics.[22][23] Kantner is also currently the President of the Kay Yow Cancer Fund’s Board of Directors, as she serves on the board alongside fellow NCAA women’s basketball official Joseph Vaszily. Kantner and Vaszily have been instrumental in encouraging their fellow officials to support the fight against cancers affecting women, as the officiating community contributed $145,000 to the Kay Yow Cancer Fund in 2022.