Three blocks of factors were considered as predictors of four year old children's (N = 286) personality, non-verbal intelligence and social behaviour in preschool: (a) personality characteristics at time 1 (T1) when the participants were three years old; (b) parental education and parenting practices measured at T1; and (c) age of child's entry to high-quality preschool. Child personality was rated separately by mothers, fathers and preschool teachers employing "The Inventory of Child Individual Differences" (Halverson et al., 2003) at T1 and one year later, at time 2 (T2). At both times, the teachers also assessed the children's social behaviour, completing "The Social Competence and Behaviour Evaluation Scale" (LaFreniere et al., 2001). Both of the parents independently filled in "The Family Environment Questionnaire" (Zupancic et al., 2004) at T1 and "The Coloured Progressive Matrices" (Raven et al., 2001) were individually administered to each child at T2 to obtain his/her non-verbal intelligence score. Child personality at age three predicted personality characteristics and social behaviour at age four, but not non-verbal intelligence. The family characteristics and the child's age of entry did not significantly improve this prediction. Child Furthermore, the child characteristics (personality, non-verbal intelligence and social behaviour) were compared between children who entered preschool early, when a one year parental leave was over, those who remained in parental care for the next two years, and those who attended non-parental care prior to preschool entry at age three. At T1, the early entry group scored lower on internalizing and higher on externalizing behaviour than did the remaining late entry groups. These differences appeared non-significant at T2. (Contains 1 figure.)