The rapid developmental changes occurring during early childhood place children at risk of emotional and or behavioural difficulties (EBD). While some preschool children sooner or later overcome the transient developmental difficulties, there is a large number of children for whom these difficulties are predictive of future developmental maladjustment. The preschool period is deemed as the optimal time to identify and reduce early signs of problems, before they develop into permanent patterns. Studies suggest that children's preschools represent a key component in building a comprehensive system of prevention and early intervention. Yet, the picture of emotional and behavioural difficulties in early childhood is rather fragmented and clinically oriented. This paper aims to present recent empirical evidence over the nature and different aspects of emotional and behavioural difficulties of preschool children (children ages 3-6 years old), and address the need to consider EBD from an educationally oriented perspective. Recent findings concerning the definition, taxonomy, prevalence, stability, comorbidity, gender and age differences, aetiological factors, identification, assessment, prevention and early intervention of emotional and behavioural difficulties are reviewed. This review will aid researchers, educators and other health professionals working in the area of EBD. (author abstract)