An alum says something unusually generous:
“If you want, I can run a practice case with you.”
Great.
Free case practice with someone who actually works in consulting.
So you prepare frameworks, mental math, and profitability structures.
You should.
Just do not assume the case is only about the case.
The offer itself tells you something...
Consultants are busy.
A full mock case can take much longer than a coffee chat.
So when an alum volunteers that time, they may simply be trying to help.
But they are also about to see you operate in a much richer situation than networking allows.
How do you react when the problem is unclear?
Do you listen?
Can you take feedback?
Do you become defensive after a mistake?
Can you communicate your logic without drowning them in detail?
Suddenly, the alum learns much more than your resume ever showed.
A case makes your working style visible.
That is why you should treat the session seriously without making it stiff.
For the mechanics of preparing for the practice itself, use How to Prepare for a Mock Consulting Case Interview.
A wrong answer may matter less than what you do next
Suppose you calculate the market size incorrectly.
The alum points it out.
You freeze.
Then you spend two minutes defending the assumption.
That reveals something.
Now imagine the same mistake.
You pause.
“Good catch. I used annual customers when I should have used monthly customers. Let me correct that and check whether it changes the recommendation.”
That reveals something too.
Recovery is part of the performance.
Consulting work is full of incomplete information, challenged assumptions, changing client input, and analysis that needs revision.
A mock case creates a small version of that environment.
So do not obsess only over being right.
Show that you can hear a challenge and move.
The feedback conversation may be more revealing than the case
The alum finishes and says:
“Your structure was fine, but your answers were too long.”
Do not respond with a five-minute explanation of why.
Ask for an example.
Clarify what better would sound like.
Then try again.
You might say:
“Could I redo my synthesis in 30 seconds?”
That turns feedback into behavior.
And it lets the alum see something interviewers care about too: whether you can adapt quickly.
For a deeper look at the signals beneath the mechanics, read Case Interview: What Interviewers Look For.
Coachability is difficult to fake.
So should you treat this like an unofficial interview?
Not exactly.
Turning a helpful alumni interaction into a high-pressure audition can make you unnatural.
The alum may genuinely just want to help.
But there is a better mindset.
Treat it like real professional interaction.
Prepare.
Show up on time.
Take the case seriously.
Listen to feedback.
Send a concise thank-you afterward.
Then implement what they told you.
That last part is easy to miss.
If you case with the same alum again and they see that your synthesis became dramatically tighter, you have shown more than improvement.
You have shown what happens when someone invests in you.
And that may be the part they remember when your name appears again.