The revised Bristol Social Adjustment Guides (BSAG) are used widely in clinical and research settings for initial recognition and classification of disturbed child behaviour. Conventional applications of the BSAG are based upon the premise that dimensions of manifest problem behaviour have generality across the age groups represented in the normative population and that the scale's various behavioural syndromes reflect distinct types of maladjustment. To test these assumptions, the BSAG'S standardization sample of 2,463 randomly selected Canadian school children was partitioned into 10 subsets of one-year age intervals from 5 to 14 years. For each independent subset, children's scores on the BSAG'S six core syndromes and two associated groupings of malbehaviour were subjected to principal components factor analysis with varimax rotation of selected factors. A similar two-factor model emerged at every age level with one factor denning a dimension of general overreaction and the other a dimension of general underreaction. The findings support the practice of using the BSAG'S composite over-and underreactive adjustment scales as primary indicators of maladjustment, and, furthermore, illuminate the cross-age patterns of continuous and varying specificity of the scale's component behavioural syndromes.Recent advances in the application of empirical classification procedures (Edelbrock & Achenbach, 1980;McDermott, 1980) have provided systems for reliable observation and analysis of children's social and behavioural disturbance. These systems rely upon information obtained through standardized rating scales completed by contextually-knowledgeable and unobtrusive observers such as parents and classroom teachers. One of the more popular rating scales, the Bristol Social Adjustment Guides (BSAG), has gained international interest, due largely to its behaviourally-oriented item content, criterion validity, and recent refinement and restandardization with 2,527 Canadian school children. The BSAG goes further than many other instruments in claiming to measure types of problem behaviour beyond the traditional acting-out vs. withdrawn dichotomy described by Peterson (1961) and Rutter (1967) and, moreover, holds the generality of behavioural disturbance to be fairly constant throughout elementary school years. This study is undertaken to test the verity of such claims.The revised BSAG is composed of 110 brief verbal terms and phrases which teachers may employ to describe children's ongoing behaviour problems in the The author wishes to thank Dr. Denis H. Stott, emeritus professor and former department head in psychology at the University of Guelph, Ontario, for kindly making the revised Bristol Social