Speech disorders or speech impediments are a type of communication disorder where 'normal' speech is disrupted. This can mean stuttering, lisps, etc. Someone who is unable to speak due to a speech disorder is considered mute. Speech disorders or speech impediments are a type of communication disorder where 'normal' speech is disrupted. This can mean stuttering, lisps, etc. Someone who is unable to speak due to a speech disorder is considered mute. Classifying speech into normal and disordered is more problematic than it first seems. By a strict classification, only 5% to 10% of the population has a completely normal manner of speaking (with respect to all parameters) and healthy voice; all others suffer from one disorder or another. There are three different levels of classification when determining the magnitude and type of a speech disorder and the proper treatment or therapy: In most cases the cause is unknown. However, there are various known causes of speech impediments, such as hearing loss, neurological disorders, brain injury, intellectual disability, drug abuse, physical impairments such as cleft lip and palate, and vocal abuse or misuse. Many of these types of disorders can be treated by speech therapy, but others require medical attention by a doctor in phoniatrics. Other treatments include correction of organic conditions and psychotherapy. In the United States, school-age children with a speech disorder are often placed in special education programs. Children who struggle to learn to talk often experience persistent communication difficulties in addition to academic struggles. More than 700,000 of the students served in the public schools’ special education programs in the 2000-2001 school year were categorized as having a speech or language impediment. This estimate does not include children who have speech and language impairments secondary to other conditions such as deafness'. Many school districts provide the students with speech therapy during school hours, although extended day and summer services may be appropriate under certain circumstances.