Issue Trees Are Dead- In Virtual Case Interviews

Issue trees are often used by consultants to help break down large or complex business issues into smaller, more manageable pieces. From there, those pieces can be put into a plan to bring about a solution to the overall problem. Some use them for case interviews, but should they in this post covid world? You may ask what Covid has to do with issue trees, but to cut to the chase, virtual case interviews. Some candidates have their initial interview virtually, and it’s becoming more and more common. But in virtual case interviews, are they still useful, or are they dead? Jenny Rae, ex-Bain consultant, gives us her take.

Issue Trees Are Dead

Issue Trees Are Dead In Virtual Case Interviews- YouTube Transcription

The issue tree is dead. That was my thought as I was reading someone else’s epitome of glory for the issue tree as they were talking about how great it is to solve case interviews. And I had this immediate reaction. The reaction came from the fact that right now the most common question I’m getting in every single one of our seminars, every single one of the coaching sessions, the live Zoom calls that we’re holding. The question that I’m getting is how do I modify what I need to do inside the case interview for a virtual environment. The issue tree is not the way to go and I will explain why.

I’m going to do so in four different sections.

  1. First of all, I’m going to talk about what the heck is an issue tree in general.
  2. Second, I’m going to talk about why issue trees are amazing, usually to solve case interviews.
  3. Third, I’m going to talk about how issue trees parallel over to real life, and why they’re great tools.
  4. And fourth, I’m going to talk about why it’s a terrible time to use issue trees for virtual case interviews.

What Is An Issue Tree?

First of all, what is an issue tree in general. An issue tree is where you start with a singular concept, usually one common theme or takeaway. A mission if you will. And you break it up into smaller pieces, and each of those smaller pieces you break up into smaller pieces. And each of those smaller pieces you break up into smaller pieces. Most issue trees that you see will have around four levels. The core mission, two or three categories coming off of the core mission. One to two subcategories off of each one of those, and then up to three or even four subcategories off of all of those.

Once it’s done, it really looks like an evergreen tree, a Christmas tree that spreads out over your paper. An issue tree is there to break up a very large concept into its much smaller pieces, but to retain the sense of the relationship between them.

Why Use Issue Trees In (Normal) Case Interviews?

So why are case interviews usually well served by starting with issue trees? Well, issue trees are very effective tools to solve problems because they take big problems, problems that are seemingly unsolvable, and they break them up into small enough pieces to do one of two things. Either cross them out because they are not relevant to the situation at hand, or dive deep into them by discovering data and information and then using that data or information to clarify a response.

So once you have the issue tree clearly laid out, it gives you an explicit road map that you can follow. Do this, do that, do this, do that. And as you are canceling things out, you’re making it easier to eliminate down to the core issues inside a case. They’re also amazing because in a normal case interview, when you’re sitting across the table from someone, they can see your thought process unfold. It appears clear, structured, and, as I mentioned before, related. You know how one thing ties to another, but how point B is distinct from point A. And it’s all there on the paper, easy and able for you to see.

What’s The Point?

Why does this matter and why does this feel like such a good process? Well, in real life, issue trees are amazing to solve real problems too. In consulting firms, issue trees are great ways to map out big problems into their smaller pieces. And once they’re broken up into smaller pieces, to assign out categories to different analysts on the team. At Bain we had on average four analysts per team: two pre-MBA and two post MBA. And we would use an issue tree structure to identify all the potential analysis that we could do to solve the big core upfront problem for the client. And then we would break up each one of those pieces into the individual analyses and then we would assign them out to different people. It’s an amazing tool, and you can really visually see if you’ve comprehensively missed something, where there are gaps, where there might be overlaps inside the case.

Why Are They Dead For Virtual Case Interviews?

In short, it’s an amazing way to create a MECE structure, where you make sure you’ve caught everything major but you haven’t left anything out. However, the issue tree is dead. I stand by this right now in virtual interviews. Why? There’s no visual cue. The only way someone can perceive that you’re structured is for you to explain it. And in an issue tree, let me give you an example of how it would sound without seeing something.

Issue Tree Example

First, we’re going to start with profit changes. We’re going to look for that into revenue and cost. For revenue we’re going to look at prices and volumes, and for costs we’re going to look at fixed costs and variable costs. For prices, we’re going to look at a few different things. For volumes, we’re going to look at a few different things. At some point, by the time you’ve gotten to layer number four, you have no idea where you are and why you should focus on this.

Instead, a simpler way to present a profitability structure would just be to start with that layer, what we call the bucket layer, and leave off some of the implied pieces, such as we want to change profit or revenues and costs. Just start with prices, volumes, variable cost, and fixed cost. Those are my four categories. Now, in the price changes there are three things that I want to explain. It retains the exact same clarity of structure, but it removes complexity that does not aid the value of solving the case. Where do you put that core theme or idea? You still state it at the beginning and you still reiterate it at the end. It’s ever present inside the case and can even be on your paper, but it no longer becomes the apex of an issue tree. Instead, it’s a much more clear way to walk through your structure simply to do buckets and sub data points.

Secondary Data Is Hard To Follow Virtually

One final reason why issue trees are dead. When data has baby data, it’s very difficult for someone to follow along with it. Already inside a structure when you’re in the case interview, you have to be incredibly clear about what you’re doing and when you move on from point one to point two. In fact, we recommend an almost over-numbering as you’re explaining your thought process. The first thing that I want to look at is prices. Inside the price category, there are three things that I want to look at. The first thing is [fill in the blank] the second thing is [fill in the blank]. That concludes the price category. Now we want to move on to category number two, which is volumes.

Using that kind of over-numbering, explicit numbering helps someone follow along with you, perceive that you’re clear, perceive that you’re structured, and helps you really quickly be able to walk through your entire structure of the case.


Ultimately, it’s possible that issue trees in the future will make a resurgence, but right now, when communication is incredibly important and you are limited in the ways that you can do it, we recommend not using the issue tree for case interviews. Issue trees are dead! If you have questions about how to adapt your interview process to a virtual environment, we would love to help. You can reach out to us at [email protected], subscribe to our YouTube channel, join us at our podcast Strategy Simplified, or most importantly see all the resources available on our website.

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Filed Under: Case Interview, Consulting Case Interview, consulting interviews