This chapter describes the use of participant observation and field notes as central methods in ethnographic research. It provides a historical perspective on the development of these methods in anthropology and sociology. It goes on to describe how to do participant observation, exemplified using a recent research project the author carried out in a school. Access, observation and discussion with research participants are described, and common challenges are explored, including ethical dilemmas. The importance of reflexivity and awareness of one’s own position as a researcher is underlined. The chapter goes on to discuss decisions which need to be made around how to take field notes, addressing both practical and ethical issues and explaining the important role of field notes in developing reflexivity. Recent studies in linguistic ethnography are described, showing how they draw on participant observation and field notes to support their claims. Critical issues and debates are identified around the researcher-generated nature of field note data, and balancing the value of recorded language data and data from participant observation. The chapter identifies the value of team ethnography in addressing some of these issues, and argues that future research needs to address these concerns directly.