This study analyzed some of the problems of measuring intelligence and verbal learning ability among Mexican-American preschoolers. These bilingual children encountered greater difficulty in correctly identifying verbal noun concepts on the Peabody Picture Vocabulary Test. Structural and idiomatic differences between the English and Spanish languages were thought to be the source of the difficulty. The study emphasized the dangers of reliance upon methods of evaluation and prediction which are not analogous to the context of the particular learning handicap.