**1. Introduction**

In this paper we tackle the difficulties present in adequately conceptualising child abuse and neglect, we provide data on its incidence and we describe the main psychopathological consequences associated with each type of child maltreatment.

Thus, we focus on the heterogeneity of the phenomenon (heterogeneity of the notion of "child maltreatment", heterogeneity of the classification criteria, heterogeneity of the different approaches that are related to maltreatment and the heterogeneity of the causes and consequences) and on the complexity that gives rise to that heterogeneity to define the child abuse and neglect.

In children and adolescents, child abuse and neglect can produce a decline in their biological, psychological and social functions. Child maltreatment in childhood and adolescence is recognised as an important psychopathological risk factor and is associated with poor psychological function in childhood and adolescence and adulthood. In this respect, we emphasise that it is wrong to believe that current knowledge has enabled the identification of clearly differentiated consequences for each type of child maltreatment. There is a high degree of co-morbidity among the different types, in such a way that many children experience more than one form of maltreatment and display common consequences. Moreover, it still needs to be clarified whether child abuse and neglect produces a general vulnerability towards psychopathology, in such a way that other factors would be responsible for the form finally adopted by psychopathology.
