Secondary Action is a crucial technical principle that involves animating small, subordinate movements that support and enrich the main action, significantly enhancing the illusion of life and physical reality. For instance, while a character is primarily walking (the main action), the secondary actions might include adjusting their glasses, fiddling with a button, or the subtle shifting of balance—all of which add texture and personality. These details make the character feel less like a puppet and more like a thinking, breathing entity.

Students are trained to identify and incorporate secondary motions that reveal character traits or add physical comedy, using overlapping action principles to ensure these motions trail and settle naturally after the main action has concluded. Technically, this requires organizing the animation layers and controls so that the secondary elements can be manipulated independently of the main body, ensuring the movement is complex and visually captivating.