The function of the conscious field remains mysterious from a scientific point of view. This article reviews theoretical approaches (passive frame theory and ideomotor approaches) that elucidate how the conscious field is intimately related to a special kind of action selection. This form of action selection is peculiar to the skeletal-muscle output system. The notion of encapsulation and how it explains many properties of the conscious field are discussed, including why the conscious field, though in the service of adaptive action, contains contents that are not action-relevant; why the field has a first-person perspective; and why the field is so thorough, in terms of its contents, the contrasts among contents, and the representation of spatial layout. The authors discuss subordinate encapsulation and the hypothesis that the conscious field is what allows for encapsulated conscious contents to influence action selection collectively, yielding what in everyday life is called voluntary behavior.