It is necessary to use specialized techniques to conduct a developmentally valid mental health assessment of the preschool-age child (ages 2–6 years). The standard approaches used for older children and adolescents, while they may seem applicable, will not be sufficient to obtain an age-appropriate and clinically meaningful assessment. Significant developmental differences between a preschool- and school-age child require a tailored approach to obtaining a history and eliciting a mental status exam. The first, and perhaps most fundamental, principle is that the preschool child does not function as a psychologically autonomous individual and remains inextricably tied to the primary caregiver for adaptive and emotional functioning. This idea was succinctly expressed by Winnicott (1965), whose famous phrase, "There is no such thing as a baby," emphasized the importance of the dyad very early in life. This adage remains applicable during the preschool period, despite the important developmental transitions in the primary relationship. Therefore, because the caregiver-child dyad more accurately represents the psychological status and functioning of the preschooler, the dyad is the most meaningful unit of observation or assessment. This means that, whenever possible, the mental status exam of a preschool child should be conducted with the child and caregiver together rather than with the child individually. While an individual play interview of the preschooler alone may be necessary in some circumstances (e.g., with preschoolers without the benefit of primary caregivers), observation of the child with the caregiver present is generally the most appropriate method.