Semi-Structured Interviews: Interview Guide, Questions and Tips
Reviewed by Prof. Dr. Alexander Holtermann · Updated 16 October 2026 · 5 min read
A semi-structured interview follows an interview guide of open questions but lets you change order, follow up and probe. Typical: 8–15 interviews of 45–60 min.
Key takeaways
- Semi-structured interviews combine a prepared interview guide with flexibility: every interview covers the same topics, but you can follow up on what participants raise.
- A good interview guide has 4–6 topic blocks with one open main question each, plus prompts and probes. It fits on one or two pages.
- Open, non-leading questions invite narratives: “Tell me about …”, “How did you experience …?”, “What happened next?”
- For dissertations, 8–15 interviews of 45–60 minutes are common; justify the number with saturation and practical constraints.
- Ethics approval, informed consent, secure recording and pseudonymization in the transcript are standard requirements.
What is a semi-structured interview?
Interviews range from fully structured (fixed questions and order, like a spoken questionnaire) to unstructured (a conversation around a single opening question). The semi-structured interview sits in between and is the most widely used qualitative method in student research.
You prepare an interview guide with topics and open questions that you cover with every participant. During the interview you are free to change the order, phrase questions in the participant’s language, skip what has already been answered and ask spontaneous follow-up questions. This makes interviews comparable across participants while leaving room for unexpected insights. Brinkmann and Kvale describe the interview as a conversation with structure and purpose, in which knowledge is produced between interviewer and interviewee.
| Type | Structure | Typical use |
|---|---|---|
| Structured | Fixed wording and order, often closed answers | Surveys by phone, large samples |
| Semi-structured | Interview guide with open questions, flexible order and follow-ups | Most dissertations, applied research |
| Unstructured / narrative | One opening question, participant leads | Life histories, biographical research |
How to build an interview guide
Derive the guide from your research question. Split the question into 4–6 topic blocks and formulate one open main question for each. Add prompts (sub-topics you want covered if the participant does not mention them) and probes (neutral follow-ups to deepen answers).
- Opening: thanks, purpose, duration, consent, recording, right to stop. Then an easy warm-up question.
- Main blocks: from general to specific, from less to more sensitive.
- Closing: “Is there anything we haven’t talked about that you think is important?” Then short demographics if needed, thanks and next steps.
| Block | Main question | Prompts | Probes |
|---|---|---|---|
| Starting university | Tell me about your first weeks at university. | Accommodation, first lectures, making friends | “Can you give me an example?” |
| Challenges | What situations have you found difficult so far? | Workload, finances, belonging | “How did that feel?” “What did you do then?” |
| Support | When you needed help, where did you find it? | Family, peers, staff, services | “What made that helpful or unhelpful?” |
Asking good questions
Your questions shape the data. Aim for questions that invite description and stories rather than yes/no answers or opinions about abstractions.
- Use silence: a pause of a few seconds often brings the most important part of an answer.
- Mirror the participant’s words instead of introducing your own concepts.
- Summarize occasionally to check understanding: “So if I understand you correctly …”
| Avoid | Why | Better |
|---|---|---|
| Do you find the workload stressful? | Closed and leading | How would you describe your workload this term? |
| Why did you drop the module? | “Why” can feel accusatory | How did you come to the decision to drop the module? |
| What do you think about inclusive teaching and digital tools and assessment? | Three topics at once | Ask one at a time |
| Wouldn’t you say that supervision is important? | Suggests the answer | What role has supervision played for you? |
Sampling and number of interviews
Participants are selected purposively: they should be able to inform your research question. Define inclusion criteria (e.g. “final-year nursing students who completed at least two placements”) and consider variation within that group.
For dissertations, 8 to 15 interviews are typical. Guest, Bunce and Johnson (2006) found that in a relatively homogeneous sample most themes were identified within twelve interviews. Do not promise a fixed number to your ethics committee without a range, and in your methods chapter describe how you assessed saturation.
Conducting the interview
Practical tips for the day:
- Choose a quiet, private place or a stable video call; test the recording beforehand and use a second device as backup.
- Plan 45–60 minutes per interview and leave buffer time.
- Bring the consent form and information sheet, or confirm online consent before you start recording.
- Keep the guide in front of you but do not read it aloud mechanically.
- Take brief notes on non-verbal impressions and write a short postscript (memo) straight after each interview.
- For sensitive topics, have contact details of support services ready.
Ethics and data protection
Interview research almost always needs ethics approval. Expect to submit your information sheet, consent form, interview guide and data management plan. In the UK and EU, recordings are personal data under the GDPR: store them securely (encrypted, on university storage), pseudonymize transcripts and delete recordings when they are no longer needed. In the US, your IRB will review the consent process and data security. Our article on research ethics covers the details.
From recording to analysis
After the interviews, you transcribe the recordings, usually verbatim or intelligent verbatim, and replace identifying details with pseudonyms. Then you analyze them, for example with thematic analysis or qualitative content analysis. Plan time realistically: manual transcription takes 4–8 hours per interview hour, and analysis of 10–12 interviews usually takes several weeks.
At /codieren you can upload transcripts, build a coding frame with definitions and anchor examples, and code passages directly. Requirements for interview studies, from ethics forms to the number of interviews, vary between institutions; your university’s own guidelines take precedence. Upload them to Professor Digital and the advice is tailored to them.
Frequently asked questions
What is a semi-structured interview?
A qualitative interview based on an interview guide of open questions that you cover with every participant, while staying flexible in order, wording and follow-up questions.
How many questions should an interview guide have?
Usually 4–6 main questions, one per topic block, plus prompts and probes. For a 45–60 minute interview, more than about 10–12 main questions is too many.
How many interviews do I need for a dissertation?
Typically 8–15 semi-structured interviews, depending on the homogeneity of the group and the scope of the question. Justify the number with saturation.
What is the difference between structured and semi-structured interviews?
Structured interviews use fixed questions in a fixed order, often with closed answers. Semi-structured interviews use a guide of open questions with flexible order and follow-ups.
How long should a semi-structured interview be?
Most last 45–60 minutes. Shorter interviews often lack depth; longer ones can tire participants and produce more data than you can analyze.
Sources and further reading
- Brinkmann, S., & Kvale, S. (2015). InterViews: Learning the Craft of Qualitative Research Interviewing (3rd ed.). Sage.
- Guest, G., Bunce, A., & Johnson, L. (2006). How many interviews are enough? An experiment with data saturation and variability. Field Methods, 18(1), 59–82.
- Clark, T., Foster, L., Sloan, L., & Bryman, A. (2021). Bryman’s Social Research Methods (6th ed.). Oxford University Press.
Your university’s examination regulations and style guide always take precedence.
Related articles
- Expert interviewsExpert interviews draw on people with specialist knowledge of a field, process or organization. They suit applied and policy questions; 5–10 are typical.
- Interview transcriptionTranscription turns interview recordings into text. Choose verbatim or intelligent verbatim, set clear rules and pseudonymize names before analysis.
- Focus groupsA focus group is a moderated discussion with 5–8 participants on a defined topic. It reveals shared views and how opinions form through interaction.
- Analyzing interview dataTo analyze interviews, transcribe and anonymise them, choose a method, code systematically, develop themes or categories and check them against the data.
- Thematic analysisThematic analysis finds patterns of shared meaning (themes) in qualitative data. Braun and Clarke describe six recursive phases from familiarisation to report.
- Pilot studyA pilot study is a small trial run of your survey or interview guide that reveals unclear questions, technical issues and timing problems early on.
