Qualitative research is often conceptualized as inherently small-scale research, primarily conducted by a lone researcher enmeshed in extensive and long-term fieldwork or involving in-depth interviews with a small sample of 20 to 30 participants. In the study of illicit drugs, traditionally this has often been in the form of ethnographies of drug-using subcultures. Such small-scale projects have produced important interpretive scholarship that focuses on the culture and meaning of drug use in situated, embodied contexts. Larger-scale projects are often assumed to be solely the domain of quantitative researchers, using formalistic survey methods and descriptive or explanatory models.In this paper, however, we will discuss qualitative research done on a comparatively larger scale-with in-depth qualitative interviews with hundreds of young drug users. Although this work incorporates some quantitative elements into the design, data collection, and analysis, the qualitative dimension and approach has nevertheless remained central. Larger-scale qualitative research shares some of the challenges and promises of smaller-scale qualitative work including understanding drug consumption from an emic perspective, locating hard-to-reach populations, developing rapport with respondents, generating thick descriptions and a rich analysis, and examining the wider socio-cultural context as a central feature. However, there are additional challenges specific to the scale of qualitative research, which include data management, data overload and problems of handling large-scale data sets, time constraints in coding and analyzing data, and personnel issues including training, organizing and mentoring large research teams. Yet large samples can prove to be essential for enabling researchers to conduct comparative research, whether that be cross-national research within a wider European perspective undertaken by different teams or cross-cultural research looking at internal divisions and differences within diverse communities and cultures.