There has been a growing trend in recent years towards the attribution of adult-like syntactic categories to young language-learning children. This is based, at least in part, on studies which claim to have found positive evidence for syntactic phrase structure categories in young children's speech. However, these claims contradict the findings of previous research which suggest that the categories underlying children's early multi-word speech are much more limited in scope. The present study represents an attempt to reconcile the findings of these different lines of research by focusing specifically on Valian's (1986) criteria for attributing the syntactic category of determiner to young children. The aim is, firstly, to replicate Valian's results regarding her determiner criteria on a new sample of seven children between the ages of 1;20 and 2;6; secondly, to investigate the extent to which children show overlap in the contexts in which they use different determiner types; and, thirdly, to compare this with a controlled measure of the overlap shown by competent adult speakers. The results suggest that Valian's criteria for attributing a syntactic determiner category are too generous and could be passed by children with a relatively small amount of limited scope knowledge. They also provide at least some evidence that a limited scope formula account of children's early determiner use may fit the data better than an adult-like syntactic account.