Peer rejection and dislike are adverse social experiences that can threaten children's basic need for belonging. This entry provides a review of what is known about these potentially emotionally damaging peer experiences, while also highlighting the complexities inherent in defining rejection and understanding its significance and impact. It summarizes selected research that has addressed the conceptualization and measurement of peer rejection and dislike, and behavioral risk factors for, and consequences of, rejection and dislike during childhood, including aggression, social withdrawal, physical appearance, gender‐nonconforming behavior, emotional difficulties, and academic problems. Other topics addressed include the social information processing sensitivities and biases that can better explain why rejection and dislike have long‐term negative consequences for emotional adjustment, and the potential for other social relationships (e.g., with parents or teachers) to buffer the negative effects of peer rejection and dislike.