How do we translate our intentions into actions? The psychology of action approach (e.g., Gollwitzer & Bargh, 1996; Hommel & Nattkemper, 2011; Lewin, Dembo, Festinger, & Sears, 1944) applies psychological theories on cognition and motivation to the investigation of behavior in order to develop answers to this question. In this contribution, we examine the origins of the psychology of action that have inspired our current approach to intentionality, our definition of goal intentions, and our epistemology. We will then introduce implementation intentions, a related type of intention that also contributes to the intentional control of action during goal striving, but that relies on different processes than mere goal intentions. Building on the conceptual distinction between goal intentions and implementation intentions, we will then review the empirical evidence demonstrating the difference between action control by goal intentions and implementation intentions.