The purpose of this study was to examine response dimensionality for a new measure of young children's early literacy skills. The Early Arithmetic, Reading, and Learning Indicators (EARLI) include six brief measures of early literacy skills. These measures were administered at three time points (October, January, and April) to children enrolled in Head Start. Responses from each of the EARLI literacy measures were analyzed by nonlinear factor analysis and DIMTEST. Results suggest that the majority of the EARLI literacy skill scores are essentially unidimensional. (author abstract)