The potential of clarification questions (CQs) to act as a form of corrective input for young children's grammatical errors was examined. Corrective responses were operationalized as those occasions when child speech shifted from erroneous to correct (E → C) contingent on a clarification question. It was predicted that E → C sequences would prevail over shifts in the opposite direction (C → E), as can occur in the case of nonerror-contingent CQs. This prediction was tested via a standard intervention paradigm, whereby every 60 s a sequence of two clarification requests (either specific or general) was introduced into conversation with a total of 45 2-and 4-year-old children. For 10 categories of grammatical structure, E → C sequences predominated over their C → E counterparts, with levels of E → C shifts increasing after two clarification questions. Children were also more reluctant to repeat erroneous forms than their correct counterparts, following the intervention of CQs. The findings provide support for Saxton's prompt hypothesis, which predicts that error-contingent CQs bear the potential to cue recall of previously acquired grammatical forms.In the course of conversation, the linguistic traffic between speaker and listener does not always flow smoothly. Breakdowns are not infrequent, typically occurring when the listener encounters difficulty with the speaker's utterance. On such occasions, listeners are liable to request clarification as in Example 1.