After her college career, Harmon first signed with Pool Comense for the 2009–10 season of Italy's Serie A1.[4] In 2012, Harmon would make the move to Lavezzini Parma.[5] After a season abroad in Australia and New Zealand, Harmon returned to Italy after signing with Le Mura Lucca. In 2017, Harmon won her first championship with Lucca.[6]
In 2008, Harmon tried out for the New Zealand national team after learning she was eligible because her mother was born in New Zealand. Harmon and former Stanford teammate Clare Bodensteiner were both named to the team shortly before the Olympics.[8] Harmon made her international debut for the Tall Ferns at the 2008 Olympics.
In 2011, Harmon took home the silver medal at the 2011 FIBA Oceania Championship. After taking home the silver, Harmon and the Tall Ferns would then go on to participate in the Olympic Qualifying Tournament in Turkey. After losses to Argentina and the Czech Republic, they failed to qualify.
In 2016, Harmon would once again join the Tall Ferns and compete in the Olympic Qualifying Tournament, with this edition in France. However, they failed to qualify again.