Cognitive therapies are now well established as a component for the treatment of a wide range of child behaviour problems. There is a great deal of evidence to suggest that deficits and distortions in cognitive processes play a role in disorders of affect and behaviour in children and adults alike. This has led to the development of many different cognitive therapy approaches which aim to influence cognitive products, structures and operations. Cognitive assessment methods continue to lag behind the developments in therapy, and there is a marked need for the development of reliable and valid measures. Empirical studies support the value of cognitive interventions, although it is recognised that most cognitive therapies include aspects of behavioural techniques, making it difficult to draw valid conclusions. Certainly, the results of recent meta-analytic studies have produced optimistic conclusions and justify the continued use of cognitive therapy methods in clinical practice, with a wide range of behavioural problems. Cognitive therapy techniques have something to offer with internalising and externalising disorders alike. Future research should now focus on the identification of methods to enhance the effects of cognitive therapies and to determine the characteristics of children who are most likely to benefit from these methods. There is some evidence to suggest that younger children may benefit less from cognitive therapies than do adolescents. This perhaps reflects differences in cognitive and language development. Further consideration needs to be given to adapting cognitive therapy methods to the developmental level of younger children. Cognitive therapy approaches are now well entrenched within many multi-component programmes for most emotional and behavioural disorders in children. The degree to which cognitive therapies add to the effectiveness of behavioural methods, however, remains to be demonstrated for many types of behaviour problem. It is also unclear whether the changes in affect and overt behaviour produced in these intervention programmes is actually related to improvements in the cognitive activities that were targeted in therapy. From a theoretical perspective, however, cognitive therapies have a high degree of face validity. If deficits or excesses in specific cognitive events or processes are found during assessment, which can be hypothesised to underlie disturbances of affect of behaviour, then there is a strong case for attempting to change these aspects of cognition.