In this article the authors propose that non-organic failure to thrive (FTT) is a growth failure secondary to feeding-skills disorder, and that this disorder is neurophysiological in origin. The symptoms of feeding-skills disorder were suggestive of an oral sensorimotor impairment which is usually present from birth or early life, but tends to go unrecognized. Data from 38 infants with non-organic and 22 infants with organic FTT demonstrated that early clinical symptoms of feeding impairment, and observed maternal and infant feeding behaviours and interactions, were similar for both groups, suggesting a need to redefine the term 'non-organic'.