Individual Differences and Personality provides a student-friendly introduction to both classic and cutting-edge research into personality, mood, motivation and intelligence, and their applications in psychology and in fields such as health, education and sporting achievement. Including a new chapter on 'toxic' personality traits, and an additional chapter on applications in real-life settings, this fourth edition has been thoroughly updated and uniquely covers the necessary psychometric methodology needed to understand modern theories. It also develops deep processing and effective learning by encouraging a critical evaluation of both older and modern theories and methodologies, including the Dark Triad, emotional intelligence and psychopathy. Gardner's and hierarchical theories of intelligence, and modern theories of mood and motivation are discussed and evaluated, and the processes which cause people to differ in personality and intelligence are explored in detail. Six chapters provide a non-mathematical grounding in psychometric principles, such as factor analysis, reliability, validity, bias, test-construction and test-use. With self-assessment questions, further reading and a companion website including student and instructor resources, this is the ideal resource for anyone taking modules on personality and individual differences.