How do individuals adjust their actions to those of other people to achieve common goals (Clark, 1996) Clearly, sharing action representations is not sufficient for successful interpersonal coordination. Whereas shared action representations allow individuals to simulate and predict others’ actions,successful joint action often requires choosing appropriate complementary actions at an appropriate time. Take rowing a canoe as an example: When rowing a canoe alone, one can coordinate the timing of left and right paddle strokes quite easily because both actions are at one’s own command. In contrast, two people rowing a canoe together must adjust to each other, because each partner has just the left or the right paddle strokes at his or her command. Knowing whether the other performs left or right paddle strokes will not be sufficient for successful coordination. Instead, to avoid going around in circles, each rower also needs to attend to the timing of the other rower’s strokes when timing his or her own. The coordination will be smoothest if each rower acquires an internal model that allows predicting the timing of the other rower’s actions in relation to his or her own.