Background: There is growing awareness and exposure in both the medical community and the lay media about the characteristics and complex needs of individuals who believe that their gender identity does not match their birth sex. Despite research and lay publications about teens with gender dysphoria and those who identify as transgender, little guidance is available regarding young (prepubertal) children with questions about their gender identity. Although many terms are used to describe these children, we have chosen to describe them as “gender nonconforming” (GNC). Objective: Primary care and developmental-behavioral pediatric providers are often the first professionals with whom young gender nonconforming children and their families discuss their concerns about their emerging gender identity. It is important, therefore, that pediatric providers be knowledgeable about the dilemmas, conflicts, and choices that are typical of these children and their families to guide them appropriately. Overview: In this special article, we present observations, informed by clinical experience, an emerging body of research, and a developmental-behavioral pediatric framework, of the complex needs of prepubertal gender nonconforming children and their families and an approach to their care. The article begins by outlining the cognitive and biological bases for gender identity development, as well as the natural history of gender nonconforming preferences and behaviors. It then sets the context for understanding the care of GNC children as an area in which developmentally sophisticated providers can play a crucial role in support of the complex developmental patterns and need for advocacy in multiple settings among these children.