This data package contains transcripts of 35 interviews with researchers from various disciplines and with various experience levels as well as cross-disciplinary support staff at six European universities. The topic of the interviews are researchers' research data management needs across the research data lifecycle. The transcripts shed light on research data management practices and needs in the phases of planning a research project, collecting, processing, analyzing, sharing, publishing and archiving data as well as reusing existing research data. Furthermore, the transcripts illuminate researchers' conception of research data and research data management as well as general processes happening at universities relating to the topic of research data management. Further information on the data package and our method can be found in the README file.