Taking the social, political, and ethical dimensions of mathematics education seriously means not only researching these issues, but also designing and assessing research with these dimensions in mind. When designing an interview study about planning in mathematics, diversity in meanings was recognized and participants and their voices were foregrounded. In this paper, the design is related to perspectives on interviews, meaning as both durable and transient, and quality criteria such as reproducibility and bias. Theoretical assumptions had consequences for how meaning was seen, but also for relevance of the chosen quality criteria. Findings suggest that not only design, but also assessment of quality in interview studies have to be discussed in relation to the theoretical assumptions the studies build on.