The use of multimethod research is becoming increasingly widespread in the social sciences, including political science, and it is part of a broader movement that has moved beyond the single focus on either qualitative or quantitative studies. In Multimethod Research, Causal Mechanisms, and Case Studies: An Integrated Approach, Gary Goertz lays out a comprehensive approach to multimethod research and to the use of case studies. The aim is to integrate qualitative and quantitative research—for instance through case studies—and to show the advantages of combining the two. Goertz does so by bringing together causal mechanisms, cross-case causal inference and within-case causal inference into what he calls the research triad of this integrated approach to social science research. In their reviews of Goertz’ book, David Waldner, Jennifer Cyr and Kendra Koivu take issues with particular aspects of Goertz’ case for multimethod and case study research, while also addressing larger methodological issues surrounding political science research.