Publisher Summary The chapter presents a review of the literature on infants' representation of objects and events suggests that striking discontinuities exist in the interpretation of the data. The importance of considering non-conceptual accounts is described and how data with toddlers constrains and reinterprets the infant data is investigated. The studies are efforts to determine what makes the search task difficult for the young child. The problem seems very simple and straightforward on the surface, but study after study has shown that this is not the case. Moreover, the chapter discusses issues of visual tracking and catching of moving objects and concludes with a discussion of the infant and toddler data in the context of others' data to arrive at an interpretation that clarifies and integrates the findings.