In the last 15 years, a combination of detailed clinical, genetic, molecular electrophysiological and immunological research has combined to result in a deep understanding of a subgroup of neurological diseases spanning the central and peripheral nervous system and which have become known collectively as the Neurological Channelopathies.Ion channels are critical membrane bound proteins that underpin many fundamental processes in the central and peripheral nervous system including action potential generation and propagation and the control of neurotransmitter release at all CNS synapses as well as at the neuromuscular junction. Ion channels are consequently essential for all motor actions, cognitive functions and sensory perceptions. Although it was originally considered that significant ion channel dysfunction would not be compatible with life, we now know this is often not the case, although severe disease can often be the result. Given the fundamental processes that are dependent on ion channel function, it is perhaps unsurprising that genetic or immunologically mediated ion channel dysfunction can result in almost any neurological symptom; patients may present to virtually any subspecialty within both adult and child neurology. The advances that have been made here have not only increased knowledge about the fundamental molecular mechanisms at play, but have also improved our ability to both diagnose and treat many of these disorders in clinical practice. Given these major advances, it is now the right time to combine this knowledge into a single HCN volume dedicated to the Neurological Channelopathies.The book will begin with an introductory overview highlighting common mechanistic themes that cut across different CNS and PNS presentations but with potential for common treatment approaches. This initial chapter considers the classification, genetics, and fundamental physiology of ion channels. Subsequent chapters present a detailed consideration of all genetic and immunological channelopathies. Each chapter will consider- Pathophysiological underpinnings - genetic or immunological- Clinical presentations- Diagnostic approach- Treatment and management