The vestibular system matures early in embryonic life but the neonate lacks postural control and co-ordination. From this it seems likely that vestibular responsiveness changes in infancy, and previous studies have suggested that such changes exist and continue throughout the childhood years. However, the overall picture is unclear due to the heterogenicity of stimuli and recording techniques employed in different studies. One of the other major sensory systems responsible for orientation is the visual apparatus, and it is recordings of eye movement which allow an assessment of vestibular responsiveness (through the vestibulo-ocular reflex). Thus vestibular maturation can only be put into a proper perspective by an appreciation of any parallel changes in visual-ocular control and by an understanding of the interaction between the visual and vestibular systems. Such co-operation implicates central control mechansisms including the cerebellum. It is now clear that such an understanding is not merely of academic interest since vestibular and balance disorders in children are not as uncommon as was previously thought. It it is the case that the normal values and the range of normal data are different in childhood, then interpretation of the results obtained from the commonly applied tests is liable to be erroneous if adult norms are applied. The present study was therefore conceived in an attempt to answer certain specific questions about the maturation of visual-ocular control mechanisms and of the vestibulo-ocular reflex in children. Specifically the slow phase velocity, amplitude and frequency of eye movements resulting from caloric stimulation and the results of testing various aspects of visual-ocular control (pursuit, saccadic and optokinetic responses) were studied. In addition the effect of optic fixation of the vestibular response and the interaction between the two systems through measurement of the phenomenon of optokinetic after-nystagmus (OKAN) in response to full field stimulation was studied.