She started her career with the Melbourne Phoenix and played with them for 5 seasons in the Commonwealth Bank Trophy. Hallinan then joined the Melbourne Vixens in 2008 in the new ANZ Championships. In 2009, Hallinan was an integral member of the Melbourne Vixens lineup that won the Vixens' first ANZ Championship Premiership over the Adelaide Thunderbirds. In July 2011, it was announced that Hallinan would be joining the Adelaide Thunderbirds for the 2012 and 2013 season. Hallinan is the current captain of the Adelaide Thunderbirds. In August 2014 Hallinan announced via Twitter that she would be marrying Basketballer Joe Ingles
In 2002 Hallinan's Australian career began by captaining the Under 16 national team. In 2006-07 Hallinan was part of the Australian Under 21 team. In 2008 Hallinan joined the Australian National Squad for the first time but failed to make the top 12. In 2009 Hallinan received the International Player of the Year. In 2013 Hallinan had a stand out year in both the ANZ Championships and on the International State. This earnt her International Player of the Year and the Liz Ellis Diamond.
Hallinan's consistently brilliant performances in the 2009 ANZ Championship Season caught the eye of national coach Norma Plummer, earning her her first selection in the nation’s top 12. Hallinan made her much anticipated international debut for the Australian Diamonds against New Zealand in September 2009, owning the wing defence position for the entire international season. Her performances on the world stage were so impressive that she was awarded the 2009 International Player of the Year Award.