Case: A fifteen year-old left-handed girl presented with right-sided focal motor seizures. Neuroimaging showed a large left hemisphere lesion compatible with a middle cerebral artery stroke of presumed perinatal origin. She was not previously diagnosed with a motor deficit, although neurological examination now revealed that it required more attention to use the affected right hand during both unimanual and bimanual movements. Methods: As perinatal stroke provides unique insight in plasticity of the brain, we performed functional and diffusion brain imaging showing reduction of pyramidal efferents from the affected hemisphere and extensive compensatory bilateral brain activations during right hand movements. Results: The activated compensatory network was extensive, comprising regions involved in higher-order motor control and visuospatial attention, now recruited during simple right unimanual and bimanual antiphase movements. Discussion: This pre-existing network for simple movements that healthy subjects only need to recruit for more complex motor actions, enabled our patient to perform simple right-handed movements. (C) 2014 European Paediatric Neurology Society. Published by Elsevier Ltd. All rights reserved.