Semi-Structured Interviews: A beginner’s guide for qualitative PhD research
Let’s be real, when you start a PhD and decide to do qualitative research, everyone just kind of assumes you know what semi-structured interviews are. Like it’s a given. No one really stops to explain them properly, and you’re left nodding along while secretly Googling it later.
Sound familiar?
Well, let’s rewind and go back to basics - because in PhD-land, we don’t do that enough. We throw around terms like “epistemology” and “reflexivity” and just hope nobody asks us to define them out loud.
So today, we’re stripping it right back. This post is all about:
What semi-structured interviews actually are
How they compare to other types of interviews
And how to actually develop your own semi-structured interview guide
If you’re planning on using them in your study (or even just thinking about it), this post will help you feel clear and confident. Let’s go.
What are semi-structured interviews?
At their core, semi-structured interviews (SSIs) are a qualitative research method that sits somewhere between the rigid structure of a questionnaire and the free-flowing nature of an open conversation.
Think of it like this: You’ve got a list of open-ended questions and topics you want to explore, but you’re not glued to that list. If your participant says something fascinating, you’re allowed to follow that thread. In fact, you’re encouraged to.
Here’s what sets semi-structured interviews apart:
They’re all about understanding the participant’s experience from their perspective.
You go in with a plan, but you stay open to where the conversation leads.
You’re not testing a hypothesis, you’re exploring meaning, depth, and nuance.
This balance between structure and spontaneity is what makes SSIs so powerful. They're widely used in social science, education, healthcare, and more - because they get results without boxing people in.
Structured vs semi-structured vs unstructured interviews
Let’s imagine interviews on a sliding scale in Table 1.
Table 1. Different interview types compared
So if you’re doing research where you want rich, detailed insights but still need a bit of guidance - you’re looking at the Goldilocks zone: semi-structured interviews.
“This balance between structure and spontaneity is what makes SSIs so powerful”
Creating your interview guide (it’s a guide, not a script!)
Here’s a common misconception: people think their interview guide has to be word-perfect, totally polished, and followed to the letter.
Nope.
A good interview guide is like a roadmap. It gives you direction, but you’re totally free to take the scenic route.
You’ll want to outline:
The key topics you want to explore
A handful of open-ended questions under each topic
Some ideas for follow-up prompts if your participant needs a nudge
“Can you tell me about your experience of…?”
“What do you mean by that?”
“How did that make you feel?”
You don’t have to stick to a rigid order. You don’t have to ask every question. The guide is there to support you, not to limit you.
Kvale’s nine question types (yes, nine!)
Steinar Kvale, who literally wrote the book on this, identified nine types of interview questions that help shape a good semi-structured interview. You don’t need to use all of them in one go, but they’re great tools to have in your kit. I’ve laid them out below in Table 2.
Table 2. Types of question in semi structured interviews
The last but one - silence - is weirdly powerful. Yes, it’s awkward. But if you can learn to sit with it, your participant will often fill the gap with something deeper than you ever expected.
Challenges of semi-structured interviews (and how to handle them)
Let’s not pretend SSIs are all smooth sailing. They’re brilliant, but they come with a few common hurdles. The good news? You can absolutely handle them with a few smart strategies. Table 3 below outlines a few of them.
Table 3. Challenges of SSIs and how to deal with them
Also: don’t forget to debrief yourself after sensitive interviews. Listening to people’s stories - especially difficult ones - is emotional work. Give yourself care too.
Why you’ll love using semi-structured interviews
Honestly? They’re one of the most human, flexible, and rewarding methods out there.
You get real, rich, emotional insight
You build rapport with participants
You stay grounded in your research question, but you’re never boxed in
And even if you’re new to qualitative research, don’t panic. You don’t need to be a professional interviewer. Like anything, it gets easier with practice. The most important skill is simply being curious and open.
So go in with a plan, stay present in the conversation, and trust yourself to follow where the story leads.
Final thoughts
Semi-structured interviews are one of the best tools in your qualitative research toolkit. They strike the perfect balance between structure and flexibility - giving you enough direction to stay on track, while allowing space for the unexpected, the emotional, and the rich insights that make qualitative research so powerful.
If you're still in the early stages of designing your interview guide or figuring out how SSIs will fit into your study, don't worry, you’re not behind, you’re learning. Keep asking questions, keep exploring, and know that you can do this.
Want more help with qualitative research methods? Come hang out on the Degree Doctor blog - we talk about all the stuff nobody explains properly.