This chapter shows how semi-structured interviews can contribute to the study of language attitudes. It pays particular attention to how understanding interviews as contextually and socially situated speech events, shaped by the spatial and temporal context in which they take place and the relationship between interviewer(s) and interviewee(s), is crucial for the analysis and interpretation of interview data. It addresses the strengths of using interviews to investigate attitudes (e.g. that they may bring to light new information, new topics, and new dimensions to established knowledge) as well as their limitations (e.g. that participants may say what they believe the interviewer wants to hear or agree with the interviewer’s questions, regardless of their content). Following a discussion of the key practical issues of planning and research design including constructing an interview protocol, choosing the language or variety to use in the interview, and presenting multiple languages or varieties in interview transcripts, it explains how the qualitative data resulting from semi-structured interviews can be analysed thematically. The chapter ends with an illustration of interview methodology on the basis of a case study of attitudes towards Cypriot Greek in London’s Greek Cypriot diaspora.