Heideggerian researchers recognize that people and their worlds are coconstructed; people make sense of their world from within it, not detached from it. The presence of one's partner in a joint interview will therefore influence the experience of participants, and will also influence the descriptions they provide. In this article, we present a reflexive discussion of two studies in which we used Heideggerian hermeneutic phenomenology to explore people's experiences of sexuality and intimacy within the context of their illness. We present the Heideggerian concepts of Dasein, authenticity and truth, and draw on extracts from our interview transcripts to exemplify the different effects of joint and one-to-one interviews. We also discuss ethical considerations regarding these different interview approaches. Heidegger's philosophy does not preferentially support either method, but helps us to be clearer about the merits and limitations of each approach. Combining both approaches provides richer understanding of phenomena.