This chapter sets out various methods for gathering important data on the language uses of participants in a research project. These methods imply interaction between students, teachers and researchers. They are used in the design of research projects based on action research, ethnography or conversational analysis, this being the case with the studies presented in the first section of this handbook. Gathering research data following these methodologies often implies preparing situations, tasks or activities that engage participants to interact around a specific theme or to mobilize certain communication skills. The methods used to gather data, as explained in other chapters, are determined to a large extent by the research questions and objectives, although in qualitative research it should be borne in mind that these will change during the process. Generally speaking, data collection in the field of language education is done in situations that try to reproduce real-life communication scenarios in which the participants make oral or written contributions that are useful for research purposes and, at the same time, beneficial for their learning process. As readers will see, there is a broad spectrum of methods, including more traditional ones such as surveys, questionnaires and interviews, through to more innovative ones such as projects, tasks, and other classroom based activities or focus groups about a particular topic. [A Catalan version of this chapter is also included in the book. For the complete volume, "Qualitative Approaches to Research on Plurilingual Education," see ED573580.]