When two people join together to perform a task, they must often develop a means to coordinate their activity, taking into account the environmental circumstances (physical and social) that constrain their ability to achieve the joint task. This ability may call for the perception of joint affordances, or opportunities for group action. In this investigation, we examined individuals ability to perceive joint affordances for a simple action walking through an aperture side-by-side with another person, without rotating the shoulders. Experiment 1 indicated the joint affordance for dyads performing this task was not equivalent to the sum of the individuals separate affordances when walking through alone. Experiment 2 suggested individuals were able to perceive the joint affordance for this task, exhibiting sensitivity to the non-additive nature of the joint affordance. The results suggest that individuals can perceive affordances for joint (dyadic) action.