The author discusses the use of hierarchical tests with learning disabled (LD) children and presents four examples to explain basic characteristics of this type of test. It is explained that a hierarchical measurement provides two associated scores - a composite score and an error of prediction score. The examples are used to portray the use of a hierarchical test in analyzing cognitive processing in normal and LD children, the process of developing a hierarchical test to identify learning problems in young children, and methods of evaluating a standardized test for the properties of a hierarchical test. (CL)