The Adaptive General Reasoning Test (Adapt-g) assesses the ability to reason using words, numbers and abstract concepts. It has been specifically designed to discriminate between candidates of above average ability, whose aptitude is being assessed for graduate level employment or higher level training. Reasoning Tests in the format of the General Reasoning Test have consistently been found to be the best single predictor of job performance and trainability in roles that require a high level of general mental ability. Combining reasoning test scores with the results from personality tests can further improve the prediction of job performance, as can the use of job sample tests and structured interviews. In roles where experience and acquired knowledge are central to effective performance, it may be particularly appropriate to combine information obtained from reasoning tests with that obtained from these latter sources.