To determine whether the reversal (RS) and extradimensional (EDS) shift behavior of 3-yr-old children is affected by the salience of the relevant training dimension, 4 treatment groups were examined. 3 differed in salience conditions: Group D contained Ss trained on their dominant dimension, Group ND had Ss trained on their nondominant dimension, and Group ND-S had Ss trained on their nondominant dimension following sensitization to that dimension. Group C constituted a control for the effects of preliminary screening and contained randomly selected nonscreened Ss. Results demonstrated that the salience of the training dimension, whether experimentally established or inferred from other behavior, significantly influences the original learning (OL) and shift patterns of 3-yr-old Ss. Groups D and ND-S were faster on OL than Group ND, and both yielded more rapid RS than EDS, whereas Group ND was comparably intermediate on RS and EDS. The implications for verbal and selective attention theories of conceptual development are discussed. (20 ref.) (PsycINFO Database Record (c) 2006 APA, all rights reserved). © 1969 American Psychological Association.