The Heroes of Olympus is especially concerned with the question of what makes a good leader. Central to this question are the underlying qualities that define virtue in the Greek and Roman sense. The Greek world, which was independent communities in constant competition, placed a high value on aristeia—being the best at what one does. The expansionist empire of Rome celebrated pietas—doing one’s duty to the state, the gods, and one’s family.

These values can seem more different than they are. Ultimately, to practice one’s excellence at the highest level (aristeia) is to fulfill one’s responsibility—or one’s duty—to the gods, the city, and one’s family, as Riordan shows through the characters’ personal growth processes and their journey to understand each other. Fulfilling one’s duty by practicing one’s excellence, in turn, leaves room for many types of excellence to not only coexist but also collaborate.

In The Heroes of Olympus, the quests reveal that different situations require different forms of leadership. What matters, ultimately, is thinking as a unit, focusing on the goal at hand, and protecting one another, to the best of one’s abilities. In some instances, Annabeth’s logic is necessary; in others, Piper’s instincts lead to the best outcome. At times, fighting the way to victory is possible.