Abstract: Discusses the history and possible future of the emphasis on hemispheric specialization, from the 1st published evidence of the functional asymmetry of the human brain (P. Broca, 1865), to research in the 1960s on split-brain surgery for epilepsy, to what are described as current myths about hemispheric duality evident in neurolinguistic programming. Current research in biological asymmetry in primates is challenging the long-held view that laterality is exclusive to humans, and has raised questions about the evolution of cerebral asymmetry for language. (PsycINFO Database Record (c) 2005 APA, all rights reserved).