The aim of the present study was to determine factors that significantly predict gap crossing in toddlers. Forward multiple regression was performed including anthropomorphic measures, walking skill parameters, walking experience, and age as independent variables and gap crossing threshold as the dependent variable. Seventy-six percent of the variance in gap crossing thresholds was explained by the amount of walking experience. No other variable significantly contributed to the amount of explained variance. Thus, walking experience is the most significant predictor of the affordance of gap crossing in toddlers. The fact that walking experience, but not age, significantly predicts gap crossing thresholds, strongly opposes a strictly maturational point of view of motor development and favours the ecological point of view, in which appropriate coupling of action and perception arises through exploration of the environment. © 2005 Elsevier Inc. All rights reserved.