Mothers of 182 children attending nursery schools completed the Behavior Style Questionnaire regarding their children. The questionnaires were rated and scored for nine temperament categories, which in turn determined temperament cluster membership. Multivariate analysis of variance was used to evaluate the nine category scores in relation to birth order position, age, socioeconomic status (SES), sex of child, and employment status of mothers. There was an overall statistically significant difference for the nine temperament category scores when children were distributed according to sex and birth position. Boys scored significantly higher for activity and for slow adaptability, while girls scored significantly higher for distractibility. These sex differences need to be considered in the establishment of temperament category norms. Temperament cluster membership was independent of all variables except SES. Significantly greater numbers of children classified within the “easy” and “slow to warm up” temperament clusters came from the upper two SES levels, while children in the ldquo;intermediate” clusters came from the lower three SES levels.