Inheritance is a feature of the object-oriented paradigm that permits substantial reuse of code. For us to have confidence in reused code, it must be adequately tested. Whilst object-oriented analysis, design and implementation techniques have received much attention in recent literature, object-oriented testing has been given comparatively little consideration. This paper presents an adaptation of the ClassBench methodology to the testing of inheritance hierarchies in C++. A small case study which applies the strategy to an inheritance hierarchy of a commercial class library is presented.