Congential myopathies, Muscular dystropies, Glycogen storage diseases of muscle, and Idiopathic and Inflammatory myopathies are presented in this volume of Neurologic Clinics. Topics include: Muscle channelopathies; Pompe disease; Congenital myopathies and muscular dystrophies; Duchenne and Becker muscular dystrophies; Distal myopathies; Limb-girdle muscular dystrophy; Fascioscapulomuneral muscular dystrophy; Myotonic dystrophy; Metabolic and mitochondrial myopathies; Sporadic inclusion body myositis; Toxic myopathies; Idiopathic Inflammatory myopathies; Approach to muscle disease.