The stability of the Kaufman Assessment Battery for Children (K-ABC) was studied by examining its performance over a 5-year interval with 16 non-handicapped children aged 45 to 61 months at the beginning of the study. Global scale stability coefficients (corrected for restriction in range) for Time 1 testing (age 4 years) and Time 4 testing (age 9 years) were: (1) mental processing composite, 0.62; (2) sequential processing, 0.45; (3) simultaneous processing, 0.71; and (4) achievement, 0.63. Repeated measures analyses of variance revealed non-significant differences in global scale means across the four test times. The results indicate a high level of stability for global scale scores from preschool (age 4 years) to elementary age (age 9 years) and from age 6 to age 9 years. Analysis of performance patterns are discussed. There are two tables of study data and a five-item list of references. (SLD)