Anxiety disorders in preschool-age children represent an important clinical problem due to high prevalence, substantial impairment, persistence, and associated risk for later emotional problems. Early intervention may mitigate these problems by capitalizing on a strategic developmental period. Elevated neuroplasticity, availability of screening tools, and the potential to modify parenting practices position anxiety as a good candidate for early intervention and preventive efforts. While some novel interventions show promise, the broad success of such programs will largely depend on parent engagement. Since parents are less likely to identify and seek help for anxiety problems compared to other childhood behavior problems, especially in a preventive manner, methods for understanding parents' decisions to participate and enhancing levels of engagement are central to the success of early childhood anxiety prevention and intervention. Understanding these processes is particularly important for families characterized by sociodemographic adversity, which have been underrepresented in anxiety treatment research. This review summarizes the developmental phenomenology of early emerging anxiety symptoms, the rationale for early intervention, and the current state of research on interventions for young, anxious children. The roles of parent engagement and help-seeking processes are emphasized, especially among economically disadvantaged and ethnic minority communities who are acutely at risk. Evidence-based strategies to enhance parent engagement to facilitate the development and dissemination of efficacious programs are offered.