Neurodevelopmental disorder is a mental disorder that affects emotion, self-control, learning ability and memory. It manifests after the individual grows. Such disorders can be genetic, such as attention deficit hyperactivity disorder, fragile-X syndrome, Down syndrome, etc., or caused due to neurotoxicants such as Minamata disease and fetal alcohol spectrum disorder. Intellectual disabilities and autism spectrum disorders also fall under neurodevelopmental disorders. The development of the nervous system is a tightly regulated genetically encoded process that is influenced by the environment. Any deviation from this process can result in such disorders and lead to potentially distinct pathologies later in life. Deprivation from emotional and social care in children, genetic influences, immune dysfunction, traumatic brain injury and nutritional deficits can cause such disorders. These can be diagnosed using chromosomal microarray analysis. Through support from therapists, counselors, families and groups, such disorders can be managed. This book covers in detail some existing theories and innovative concepts revolving around neurodevelopment disorders. The objective is to give a general view of the different aspects of their pathogenesis, diagnosis and management. It will help the readers in keeping pace with the rapid changes in this field.