Young children's initial categories often are not identical to the adult category labelled by the same word. Eventually, children's categories must evolve to correspond to the adult standard. The purpose of this study was to consider the relative effectiveness of four input strategies in inducing the child to learn the adult-appropriate label and begin to form a new category. Fifty-six children aged 2;0 were taught new labels for objects that they included in categories labelled by different names. Comprehension and production post-tests were then administered. As expected, the most effective strategy involved labelling an object and providing both a physical demonstration and a verbal description of important attributes that made the object a member of the adult-appropriate category. The label plus physical demonstration strategy was next most effective. Neither the label plus verbal description strategy nor the label only strategy was effective for children of this age. Results also indicated that these 24 month olds did not yet honour the convention of mutual exclusivity of basic level categories.