In its first edition this book successfully enabled readers, with little or prior kwledge of computing or statistics, to develop reliable and valid tests and scales for assessment or research purposes. In this edition, the author has thoroughly updated the text to include new recent advances in computer software and provide information on relevant internet resources. The book contains detailed guidelines for locating and constructing psychological measures, including descriptions of popular psychological measures and step-by-step instructions for composing a measure, entering data and computing reliability and validity of test results. Advanced techniques such as factor analysis, analysis of covariance and multiple regression analysis are presented for the beginner. An Introduction to Psychological Tests and Scales provides a clear, concise and jargon-free primer for all those embarking in fieldwork or research analysis. It will be an invaluable tool for undergraduates and postgraduates in psychology and a useful text for students and professionals in related disciplines.