Superior (10 girls, 10 boys), average (10 girls, 10 boys), and poor (10 girls, 10 boys) spelling ability groups were identified in first (age 6) or third (age 8) grade and assessed annually for four years. In separate analyses, a simultaneous set of phonological, orthographic and morphological predictors, a simultaneous set of pseudoword spelling and word-specific orthographic spelling predictors, and a simultaneous set of real-word and pseudoword reading accuracy and rate predictors jointly predicted individuals’ spelling ability group (superior, average, or poor) from first to sixth grade. Results are discussed for significance of results for Triple Word Form Theory (relationships of multiple language skills to spelling development), advantages of multivariate approaches that analyze a set of joint predictors, and importance of designing studies so that findings can be generalized to specific regions of the distribution — upper, middle, and lower — rather than the entire distribution of spellers in an unreferred sample.