Children with Attention-Deficit Hyperactivity Disorder typically present with shorter attention spans, impulsivity and hyperactivity. It is a neurodevelopmental disorder that affects children and adolescents but often continues into adulthood. Autism is a developmental disability that affects how individuals perceive the world and interact with others, with 1 per cent of people on the autistic spectrum. Children with Developmental Language Disorder present with a significant impairment in learning and using language, which is unlikely to resolve, particularly without specialist help. Children vary in the level or degree of hearing loss, which might be described as mild, moderate, severe or profound. Some hearing losses affect all frequencies equally, while others may affect a specific range. Vision impairment where a child is blind or partially sighted might arise from damage to or dysfunction of the eye, optic nerve or the brain. The chapter also presents an overview on the key concepts discussed in this book.