While the selection of interviewees, development of questionnaires, and generation and transcription of interview data is not meant to be as robust as would be in the case of a formal study, you will still have to make informed decisions around (1) who you will talk to, (2) for what purpose, and (3) what kinds of information you’d like to learn.

We therefore recommend carrying out interviews after you’ve identified relevant stakeholders to speak to and drafted a plan detailing your questions and approach.

Examples of rapid-inquiry interviews can include reaching out to experts or practitioners involved in existing interventions or delivery of services that relate to your problem area (such interviews are a great way to get a sense of what works, what doesn’t, and why.)

You might also want to leverage interviews to speak directly with potential end-users of your solution, who may be end-users of an existing (perhaps underperforming) service or product. This helps generate first-hand knowledge with regard to problems and/or opportunities.

Further inspiration

IDEO. Interview, Design Kit.
General interview guidance

IDEO. Expert Interview, Design Kit.
Expert interview guidance

Harvard University. Strategies for Qualitative Interviews
In-depth reading on qualitative interviews