Book excerpt: This Handbook offers a comprehensive overview of state-of-the-art research methods and applications currently in use in political science. It combines theory and methodology (qualitative and quantitative), and offers insights into the major approaches and their roots in the philosophy of scientific knowledge. Including a comprehensive discussion of the relevance of a host of digital data sources, plus the dos and don’ts of data collection in general, the book also explains how to use diverse research tools and highlights when and how to apply these techniques.