Learning disabilities are a group of conditions diagnosed when the individual's achievement in reading, mathematics or written expression is substantially below that expected for his/her age, schooling and level of intelligence. Learning disability does not include learning abnormality resulting primarily from communication disorders, impaired vision or hearing, social or emotional disturbances or cultural differences.A number of classification systems of learning disabilities have been proposed. A clinical-neuropsychological system recognises 5 types of learning disorders based on abnormalities of: (i) phonological processing; (ii) spatial cognition; (iii) executive function; (iv) social recognition; and (v) long term memory.Underlying abnormalities of cognitive processes, mostly auditory and language processing but also visual-perceptual abnormalities, are frequently present in individuals with learning disabilities. Comorbid conditions include attention deficit hyperactivity disorder, conduct disorder and social skills abnormalities.Learning disabilities can be a result of a number of conditions affecting the CNS, but the disorder is predominantly genetically transmitted. Chromosome 6 has recently been implicated in reading difficulties. A number of biological abnormalities have been found in patients with learning disabilities. Anatomical abnormalities include reversal of normally present brain asymmetries and the presence of foci of cerebral microdysgenesis and ectopias. Abnormal regional brain glucose metabolism has been demonstrated in patients with reading difficulties. Neurophysiological abnormalities include abnormal cognitive eventrelated potentials and possible abnormalities of the magnocellular visual pathway.Treatment modalities for learning disabilities include cognitive-educational psychological and pharmacological measures. Although there are no medications directly affecting the learning ability of these patients, central stimulants, clonidine or antidepressants may enhance learning ability through an effect on frequently present comorbid conditions.The prognosis of a patient with learning disabilities depends on the severity of the disability, intelligence level, the presence or absence of comorbid conditions, and environmental support.