Given executive function?s (EF?s) link to higher-order cognitive processes and control, it comes as no surprise that EF is a foundational and all-encompassing neurocognitive development linked to positive academic achievement, social understanding, relationships, and developmental psychopathologies. However, access to a comprehensive and valid measure of EF is limited in infants and toddlers. The objective of the present research is to develop an EF battery capable of examining the structural and theoretical underpinnings of EF starting in the toddler years. A battery of 9 tasks involving minimal language requirements in pursuit of goal-directed behavior focused on resisting a prepotent response will be administered to two-hundred and forty 14-, 18-, and 24-month-olds. Competing models of EF development will be tested by examining whether the patterns from the observed data match hypothesized patterns predicted by several theoretical frameworks. A key element of this proposal is to test the Social Representational Framework, which proposes that the development of representational abilities (e.g., language, gesture) forms the foundation for the transition to more controlled behavior regulated by forming and reflecting on task-relevant representations. Specifically, this research will assess whether the best fit to describe performance across multiple EF tasks in toddlerhood is a unitary EF factor related to developing social-communicative representation (e.g., language, gesture, joint attention) and other abilities that draw on representation in this period (e.g., theory of mind, or the understanding that others have mental states that guide behavior).