Assessment techniques range from the inevitable interview to graphology and even astrology, yet for over 50 years it is aptitude and other psychological tests which have consistently proved their worth. Selecting and introducing them, however, can present major practical difficulties. The choice is wide, many tests are computerised and training is costly. This guide, written by experts with experience in industry, commerce and the public sector, aims to provide useful help. It considers the underlying principles, the different kinds of tests, how to assess them, their costs and benefits, and their use with other methods (as in assessment centres).