Hyperbaric Oxygen Treatment (HBOT) has been used since 2004 for some patients diagnosed with autism and other co-morbid medical issues.Autism is a complex neurological disorder that typically occurs within the first three years of life that results in usually severe developmental disability. Its incidence in the population is estimated to be 1 in 500 with a prevalence of 75% boys to 25% girls. The ensuing effects of the disease result in severe impairment in areas of social interaction and communication and in some individuals self-injurious behavior may occur.Presently there is no effective cure for this disease, as little is known as to the etiology. Diet, psychotropic medications and other regimens have been tried with mixed and often disappointing results. Recently hyperbaric oxygen therapy (HBOT) has shown to be of possible benefit in the alternative treatment of this disease.Initial results of the HBOT treatments were objective improvements in a variety of diverse phenomenons. Each child demonstrated global reduction in aggressive behavior. Parental summaries all stated a substantial decrease in tendency to rage or exhibit tantrums. All children were reported to be easier to engage when the parent wished to initiate communication with marked improvement of direct eye contact. All three children enrolled in a school program displayed higher achievement with better performance and less instruction in classroom assignments. All children were improved with regard to understanding verbal commands. Reasoning abilities were noticeably enhanced in all individuals.The popularity of using hyperbaric oxygen therapy to improve autism is growing despite evidence of efficacy.