Expanded and updated, this best-selling textbook presents a comprehensive and accessible introduction to the key research methods – both qualitative and quantitative – used in psychology and across the social sciences. Research Methods in Psychology is organized into four coherent sections: Part I considers the relationship between psychological theory and research methodology, from both a practical and ethical viewpoint. Part II explains how to collect data using the major types of research design, and at the same time introduces the philosophical principles underlying them. Part III offers an invaluable guide to the traditional techniques of data gathering in psychology, as well as featuring less common techniques such as diary method, focus groups, ethnographic approaches and action research. Part IV covers the issue of data analysis, clearly explaining the logic of statistical testing and the relationships between methodology and statistics, avoiding over-complicated formulae and focusing upon what can legitimately be inferred from commonly used psychological statistics. The book is illustrated throughout with examples from current research and combines step-by-step advice, exercises and lists of further reading. Written in a lively and accessible style, this test should be essential reading for all methods courses in psychology, nursing, health studies and others that draw on the array of research techniques available in psychology.