The development of response inhibition was investigated using a computerized go/no-go task, in a lagged sequential design where 376 preschool children were assessed repeatedly between 3.0 and 5.25 years of age. Growth curve modeling was used to examine change in performance and predictors of individual differences. The most pronounced change was observed between 3 and 3.75 years. Better working memory and general cognitive ability were related to more accurate performance at all ages, but relations with speed changed with age, where better cognitive skills were initially related to slower responding, but faster responding at later ages. Boys responded more quickly and were more accurate on go trials, whereas girls were better able to withhold responding on no-go trials.