How to prepare case interviews under intensive working schedules

This is a very real situation, and almost everyone who later succeeds in laterals goes through some version of it. You are not doing anything wrong.

A few grounded thoughts, based on how MBB actually works and how interviews are evaluated.

On rejecting or managing staffing

There is no elegant way to “decline” a case once the machine is moving. Anyone telling you otherwise is overselling optionality. What you can sometimes do is manage scope, not staffing.

If you have a staffing manager, PL, or EM you trust, flag capacity constraints early and concretely. Ask whether partial staffing, a narrower role, or a later ramp-up is possible. Frame it around delivery quality and sustainability, not personal plans. Sometimes this works, sometimes it does not.

If it does not work, accept it fully. Half-committing to a case while secretly preparing is the fastest way to burn energy, underperform, and still feel underprepared.

On preparing with very limited time

The good news is that you are not starting from zero. As a one-year MBB consultant, the goal is not to “learn casing.” It is to re-activate clean habits and avoid obvious failure signals.

With three weekends and short weekday windows, preparation has to be surgical.

• Weekdays (30–60 minutes, mornings):
  No full cases. Use this time for sharp drills only:
  • Structuring prompts in 5 minutes, out loud
  • Mental math and breakevens
  • 30-second syntheses of exhibits or short cases
    This keeps the muscle active without draining you.
• Weekends:
  Do fewer cases, but treat them seriously.
  • 1–2 full interviewer-led cases per weekend
  • Spend more time reviewing structure, hypotheses, and synthesis than doing additional cases
  • Identify the same 1–2 issues across cases and fix only those

Most candidates waste time chasing volume. Under your constraints, that is exactly what you should not do.

What interviewers will actually judge

At your level, interviewers are not looking for brilliance. They are looking for:

• Clear, simple structure
• Calm communication under pressure
• Business judgment and prioritization

Most lateral failures happen because candidates overcomplicate, rush, or try to “perform” instead of think.

If you keep your approach simple and controlled, this timeline is absolutely sufficient for a first round.

Finally, do not underestimate the ROI of one or two focused mock interviews with someone senior or ex-MBB. Under time pressure, fast calibration beats weeks of unguided prep.

Hi there,

This is a very real dilemma and you’re not alone in it. A few thoughts that might help you think about this pragmatically.

1. On rejecting the case: there’s no magic way to “skillfully” reject staffing, but you can sometimes manage it rather than refuse it outright. If you have a staffing manager or mentor you trust, it’s reasonable to flag capacity constraints early and ask whether a lighter role or partial staffing is possible. Framing it around sustainability and existing commitments rather than external interviews is usually safest. That said, at MBB this doesn’t always work, and you should assume you may still be staffed
    
2. If you’re working with only three weekends and limited weekday time, the key is to be very targeted. You don’t need volume, you need sharpness. Use weekday mornings for short drills: exhibit interpretation, mental math, and 30-second syntheses. Avoid full cases on weekdays. On weekends, do one or two full cases under time pressure and spend more time reviewing structure and synthesis than doing more cases

Given your background, you’re not rebuilding from scratch. The goal is to re-activate good habits, simplify your approach, and get comfortable again with live casing. In this situation, a couple of focused mock interviews with someone senior or a coach can be very high ROI, because they help you quickly recalibrate without wasting time on unnecessary prep.

Best,
Evelina

Hi!

A few thoughts, keeping this practical and realistic.

First, some perspective, since you’re already at MBB, you’re not starting from scratch. You already have the core case interview muscle, this is about sharpening, not rebuilding.

1) On rejecting the case: My personal opinion is not to reject the case, but if you really want a break, you can always take some personal time off. I wouldn’t over-optimize on trying to avoid staffing at this point.

2) On the interview prep with limited time: Given your constraints, I’d avoid full-length cases and focus on targeted drills:

• Identify 1–2 weak areas that actually matter (e.g. initial structuring, brainstorming, market sizing, synthesis)
• If you’re not sure what those are, one session with a coach can be high ROI just to diagnose gaps quickly
• Don't forget to spend some time on fit / PEI stories. Suggest not to skip this. At your level, fit would matter a lot, since they'd likely know you can already do well in cases, being in one of the MBB 

The goal is precision, not volume. You don’t need to “do more cases”; you need to remove rough edges.

Lastly, manage your energy. If you’re finishing at 1am, consistency is key. A focused 30 - 45 mins beats an exhausted 3-hour session.

All the best! And good luck with the interviews!

On rejecting the case:

Don't. Here's why.

You're one year in. You don't have the political capital to be picky about staffing. Partners talk. If you suddenly become "unavailable" right when a big case needs bodies, people notice. And if your lateral move falls through (which happens more than you'd think), you've now damaged your standing at your current firm for nothing.

The only clean ways out:

• You have a pre-approved vacation that's already on the books
• You have a genuine personal/family situation

Trying to manufacture an excuse is risky. Consulting is a small world. I've seen people get burned when their current firm found out they were interviewing, sometimes from someone at the target firm mentioning it casually.

Your real prep plan:

• Target 5-6 live cases each weekend with a strong partner. A fellow consultant, an ex-MBB friend, someone who'll push you.
• After each case, spend 30 minutes on targeted drills for whatever was weak. Math slow? Drill math. Structure sloppy? Do 5 more solo structures.

What to deprioritize:

You don't need to learn frameworks. You don't need to practice 30 cases. You need to shake off rust and get your interview rhythm back.

The things that trip up lateral MBB candidates aren't case mechanics—it's:

1. Sounding rehearsed or robotic
2. Not having a tight, credible story for why you're switching

One more thing:

Three weeks is tight but doable. I've seen people with less time get offers. But if you go in exhausted and underprepared, you'll blow it and have to wait another year to re-apply.

If this interview matters to you, protect your energy the week of the interview. Do whatever you need to do like work from home one day or take two days off. The intensive case will survive without you for a couple of days. 

This is the toughest spot to be in—the brutal irony of needing to find time to exit while the current job demands 110% of your time. It feels impossible, but we see this transition successfully executed often.

Regarding rejecting the new case, I strongly advise against it. At the one-year mark, especially when interviewing for a competitor, signaling discomfort with staffing or workload usually rings alarm bells with the Partner group or the leadership team. You risk triggering an informal exit management discussion before you’ve secured the offer. Instead of rejecting the case, focus on managing your hours within that intensive engagement. Be clear with the engagement manager (EM) that you must protect a few hours here and there for administrative tasks, and then treat your scheduled 1 am bedtime as the hard stop it needs to be, no matter the immediate deliverable.

Since you are already at MBB, you are not learning the fundamental logic—you are re-calibrating. This means your preparation must be ruthlessly efficient and focused on conversion speed. Leverage the limited windows you have:

1. Morning Hour (Focus: Mechanics and Speed): Use this 60 minutes for rapid-fire drills. Mental math exercises (multiplication, percentages, CAGR), and, crucially, reviewing core frameworks (M&A rationale, entry strategy) and practicing structuring them verbally under time pressure. Do not waste the morning slot on full live practices; save that deep cognitive load for the weekend.

2. Weekends (Focus: Target Firm Style): You need high-leverage practice here. Schedule 4-6 full cases with a partner who understands the nuances of the target firm (e.g., if you are moving from BCG to McKinsey, you need specific practice on highly hypothesis-driven, interviewee-led cases). The goal is to identify and eliminate the two or three most common mistakes you make under pressure (e.g., getting sloppy with MECE, missing the high-level synthesis).

You already have the core skills. Your challenge is stamina and precision under stress. Focus on high-quality repetitions in those limited windows.

All the best with the transition.

Hi,

I was in a similar situation - I was at KPMG corporate finance working full time and recruiting for McKinsey. And then at McKinsey, I was preparing for GMAT/business school when fully staffed. It's tough, but you have several pragmatic options.
1. Prep for 1h in the morning before the day starts. I used to do this at KPMG: I actually did 1h daily mock interviews here at prep lounge. 1h was just enough to give/take a case, but it was moving me ahead.
2. Avoid staffing strategically - take PTO that would make you unstaffable, or take vacation (mention family reasons). To prepare for business school, I actually took 3 weeks completely off because I was unable to carve any time out during the week.
3. Devote your Saturday for preparation (seems like you already have a plan for that).
You've got this!
Kateryna

1. based on current staffing conditions this would typically put you down the path for a riskier review this cycle. A) mention family or health issues, b) schedule unstaffable holiday schedule : e.g., 3 days off, followed by three days off one week later. That should give you at least three weeks of Leeway but in a really ugly way
2. you shouldn’t really need to prep that much for a competing firm. Areas I’ll typically brush up on are a) the mechanics and habits of a case that we don’t really do consistently while working - such as reading back the structure and math, talking out loud about your hypothesis, and interpreting charts out loud, b) math - market sizing, profit break evens. U can definitely do this in half a day