In this chapter, we examine how the researcher influences the relationship between themselves and their participants, focusing on the subsequent co-production of data. We present two case studies that focus on language variation and identity. The first is a study of phonetic variation and identity in a British adolescent community. The second is a study of second dialect acquisition and identity among British women in the USA and North American women in the UK. We explore some of the issues surrounding researcher-participant dynamics in this reflexive turn in social science research, discuss two case studies in terms of researcher-participant relationships, and touch on the broader implications of our analyses for research in applied linguistics. We suggest that foregrounding the interaction between researchers and participants can sometimes offer further insights into social and linguistic phenomena. In doing so, this perspective transforms the researcher-participant relationship into a source of data, rather than a source of potential bias.