The authors investigated the prevalence and characteristics of children who experience or who have experienced imaginary companions. For the study, a self-administered questionnaire that sought information regarding the characteristics of children with and without imaginary companions was completed by 478 parents of children within the age range of 3 to 9.5 years. A significantly larger number of children with imaginary companions were reported to be first-born children, to be very imaginative, to incorporate myth in their play, and to explain events as magical. Overall, these results are interpreted to indicate that birth order, combined with characteristics such as imaginativeness and a predisposition to engage in fantasy, characterizes children with imaginary companions.