PART ONE: FOUNDATIONS: WHAT METHODOLOGY IS AND DOES Inference and Warrant in Designing Research Methodology and Social Science Knowledge Testing, Confirming and Falsifying Perspectives on Findings from Social Research PART TWO: DESIGNS: THE MAIN TYPES OF RESEARCH DESIGN Types of Research Design Variable-Oriented Research Designs Case-Based Research Designs Comparative and Case-Oriented Research Designs Concept Formation PART THREE: ACHIEVEMENTS: WHAT RESEARCH MAKES INFERENCES TO Why Ideas about Explanation Matter for Methodology Basic Forms of Explanation Mechanisms, Contexts and Trajectories Warranting Explanations Between-Case and within-Case Strategies Interpretation Warranting Interpretations PART FOUR: SYNTHESIS: COMBINATIONS AND TRADE-OFFS Combining Research Designs Trade-offs in Research Design