The benefits of performance appraisal in the business world have caused an upsurge of books and programs for use in management, but few of the methods described bother to verify that the underlying psychology on which they are based holds true. A Cognitive Approach to Performance Appraisal is a careful and thorough investigation of appraisal decisions. The evidence described will be invaluable to all those involved in assessing the validity of particular performance 'packages' for use by themselves or their clients and to other researchers in appraisal techniques.