Voluntary motor actions aim at and are thus governed by predictable action effects. Therefore, representations of an action's effects normally must become activated prior to the action itself. In 5 psychological refractory period experiments the authors investigated whether the activation of such effect representations coincides with the response selection stage of information-processing theories. Participants performed 2 choice reaction tasks, separated by variable stimulus onset asynchronies. The authors varied the compatibility between responses and forthcoming sensorial effects (Experiments 1, 2, 3, and 5) or between responses and effect-resembling stimuli (Experiments 4 and 5) in one of the tasks. They observed that compatibility influences from forthcoming (anticipated) response effects were located within the response selection bottleneck, whereas compatibility influences from action-preceding (perceived) effects were due to processes before the bottleneck. These results point to a crucial role of the endogenous activation of action-effect representations for the selection of voluntary motor responses.