Hearing impairment is the partial or total loss of hearing. Chronic ear infections are considered to be the chief cause of hearing impairment. Syphilis, rubella and cytomegalovirus infections can also result in hearing loss in children. The diagnosis of hearing loss is established on the basis of hearing tests. If a person is insensitive to sound around 25 decibels even in one ear, it is classified as hearing impairment. Hearing loss is of three types - sensorineural hearing loss, conductive hearing loss and mixed hearing loss. 50% of all cases of hearing loss occurring globally are largely preventable through public health actions. All newborns should be tested for hearing loss. By providing proper care during pregnancy, immunization, avoiding certain medications and loud noise, hearing loss may be prevented. For those with hearing impairment, sign language, cochlear implants, lip reading, hearing aids and subtitle use must be promoted. There exists no treatment for the sensorineural hearing loss arising due to genetic defects, age or noise. Certain surgical interventions such as correction of superior semicircular canal dehiscence, surgical excision or vestibular schwannoma or acoustic neuroma, stapedotomy and stapedectomy, etc. may be used for the remedy of the condition. This book is compiled in such a manner, that it will provide an in-depth evidence-based approach to the understanding of hearing impairment. From theories to research to practical applications, case studies related to all contemporary topics of relevance to this condition have been included in this book. With state-of-the-art inputs by acclaimed experts of audiology, this book targets students and professionals.