Convenience, applicability to multiple informants and ability to gather information across long time intervals has made behaviour rating scales an important part of the identification of AD/HD. Aim: The study investigates whether two of the most widely used screening tools for AD/HD reliably identify children with AD/HD. Method: Parents of 170 children diagnosed with AD/HD aged 6-17 completed: the “AD/HD Rating Scale IV” (DuPaul, 1998) and the “Child Behaviour Checklist” (CBCL; Achenbach 1991). Results: One third of children receiving the diagnosis of AD/HD were reported by their parents to fall in the abnormal range of the CBCL and almost half of them to fall in the abnormal range of the AD/HD Rating Scale IV. The correlation of the two screening tools was found to be r=.704 (p=0.01). Conclusions: Although AD/HD is one of the most well-studied disorders with several assessment strategies being used, the field is challenged to further improve the identification process based on behavior rating scales, in order to lead to an accurate diagnosis of AD/HD.