Early childhood caries (ECC) is rampant caries of the primary dentition of infants and toddlers. ECC represents a serious problem in pediatric dentistry. Not only because of its rapidity but also because of age of affected children. ECC involves the maxillary primary incisors within months after their eruption and spreads rapidly to involve other primary teeth. It is a multifactorial, transmissible and infectious disease that has recently been under scrutiny in the literature. The microflora, substrate, saliva and host are key factors involved in the pathogenesis, together with the immature host defence system and developing bacterial flora. Immature enamel surfaces and developmental defects of enamel should also be considered in the aetiology. The early implantation of mutans streptococci, the use of a feeding bottle containing sugary solutions and prolonged breast-feeding, especially at night, are important predisposing factors. High risk children belong to ethnic minority groups and to low income families with poor parental behaviors and attitudes. Clinical management should be planned according to age, extent of lesions, compliance of primary caregivers. Cases of early childhood caries need comprehensive restorative management and preventive treatment.