The study book provides a systematic guide for students planning a quantitatively oriented empirical investigation in the field of linguistics/language teaching research. Each individual step is explained in detail: finding a precisely defined research question, considering scientific quality criteria, the methods (observation, surveys, experiments, and the use of text corpora) and instruments for data collection, data analysis and its statistical preparation, as well as writing the research report. For the second edition, the statistics chapters have been specifically adapted to the needs and prerequisites of the students, and newer data collection instruments have been added. Each chapter includes exercises with solution hints and detailed references to further literature.