The long-chain polyunsaturated fatty acids (LC-PUFAs) docosahexaenoic acid (DHA) and arachidonic acid (ARA) occur in high levels in the brain and play a key role in brain growth and the operation of neurotransmitters. Infants supplemented with DHA show improved language and communication skills, and there is accumulating evidence that the early development of executive functions such as planning, working memory, and attention control are influenced by LC-PUFAs, especially DHA. Several studies have found significantly improved means-end problem solving at 9 and 10 months in infants given DHA-/ARA-supplemented formula, and similar results were shown for infants whose mothers were supplemented with DHA during pregnancy and breastfeeding. Long-term benefits of LC-PUFA supplementation in infancy have been reported in children aged 3-6 years. Follow-up studies of infants given DHA-/ARA-supplemented versus control formula have shown better performance on tests of impulsivity and attention control in the supplemented children, with indications of a dose-response relationship for DHA. LC-PUFAs (especially DHA) in postnatal infant diet influence the development of executive functions and other higher-order cognitive abilities, and have a long-term influence on the development of attention and information processing in later childhood.