The law of Prägnanz states that “psychological organization will always be as ‘good’ as the prevailing conditions allow” (Koffka, 1935, p. 110). What ‘good’ means, however, is not defined further. We clarify this definition by proposing that Prägnanz is about maximizing the efficiency of process and outcome. This includes both (a) spending minimal resources during the process of organization and (b) maximizing the usefulness (i.e., informativeness, functional relevance) of the organizational outcome. We propose a range of organizing principles, combining prior information (i.e., grouping laws, visual templates, and mental concepts) with the incoming visual input, that allow the viewer to come to the most prägnant percept possible under the current conditions (i.e., input, person, context, and their interactions). We will demonstrate that this view is compatible with hierarchical predictive coding theories of perception and we will discuss how to test it empirically.