This is a comprehensive guide to quantitative research, rooted in the author's own teaching and research. In particular, it challenges both the student who does not do numbers and the student who does nothing but numbers (and who therefore fails to interpret or challenge his/her results). The book shows how all educational researchers need to do quantitative research, even if only in the sense of reading other people's research findings. In fact, the book argues that the conventional distinction between primary and secondary research data is inadequate, since there is enormous need/opportunity for conducting research through using and reinterpreting secondary data. This leads to one of the main selling points of the book - Gorard's idea of the idle researcher, who makes valuable contributions to the research literature by using data gathered by other researchers.