The purpose of this study was to evaluate the effectiveness of two different psychological skills training (PST) packages in enhancing mental toughness among three youth-aged (under 15 years old) Australian football teams. We compared a program targeting the keys to mental toughness identified previously (Gucciardi, Gordon, & Dimmock, 2008) with a more traditional PST program targeting self-regulation, arousal regulation, mental rehearsal, attentional control, self-efficacy, and ideal performance state as well as a control group. Overall, both intervention groups reported more positive changes in subjective ratings of mental toughness, resilience, and flow than the control group. Similar ratings for mental toughness were reported by the parents and coaches. Both PST packages appeared to be equally effective in enhancing mental toughness.