Most candidates prep fit as a flashcard stack of 40 prompts. Interviewers do not. They score a short list of published dimensions, and the question you hear is only the opener. The points land on the follow-up.
This is the question bank: recurring prompts grouped by what the sheet scores, the probe each invites, and two fully worked spoken answers. Story craft lives in the behavioral interview guide; McKinsey depth in the PEI guide. Learn the bucket before you open your mouth.
What firms publish (and what they do not)
Firms are more explicit than prep folklore admits, and vaguer than a 50-question list pretends.
| Firm | What they say they assess in the non-case portion | Primary source |
|---|---|---|
| McKinsey | Personal Experience Interview with two prepared examples per published theme (impact, drive, leadership, and related areas on the careers page) | McKinsey interviewing |
| BCG | Skills interview on experience, skills, and motivation; answers reviewed against values and "core competencies" | BCG interview process |
| Bain | Intellectual curiosity and entrepreneurial bent; in all cases, a clear reason you want Bain specifically; behavioral questions on past challenges | Bain interviewing |
| Deloitte | Track record of achievement, communication, leadership and teaming, aptitude for the role; STAR structure encouraged | Deloitte behavioral tips |
What they do not publish: office-level score sheets, fit-versus-case weights, or a canonical "30 questions" list. Treat Glassdoor compilations as folklore. Treat the table as the map.
How to use this bank
Before you rehearse, name the score target in one phrase, then the probe you expect. If the draft cannot survive that probe, rewrite it. The opener is cheap; the second and third minutes fill the box.
Ned's rule. If you can swap the firm name and the answer still works, you have not answered a why-firm question. If you can swap the story and the follow-up still feels hard, you have not prepared a behavioral story. Prep the probe, not the prompt.
Cluster 1 — Motivation (why you are in this room)
These land in every first round. Bain asks for a reason you want them specifically. BCG's skills interview covers motivation. Deloitte tells you to use the conversation to learn about the firm.
| Prompt you hear | What it is scoring | Probe that usually follows |
|---|---|---|
| Why consulting? | You chose this trade for a reason you can defend against banking, industry, or a startup | "Why not stay where you are?" or "What would make you leave consulting in two years?" |
| Why this firm? | Specificity that dies if you swap logos | "What would change if you got BCG instead?" or "Which practice / city, and why?" |
| Why this office? | A constraint or staffing fact you actually have | "Would you take New York if it came first?" |
| Why this practice / why generalist? | You understand the work, not the brand | "What case mix are you expecting in year one?" |
| What questions do you have for me? | Curiosity that is not Glassdoor | They will answer; your next question shows whether you listened |
Pass shape (60–90 seconds for why consulting; 45–75 for why firm). One trade-off you considered, one firm-specific fact (conversation, staffing model, practice mix, published operating principle), one risk you already accepted. Stop. Leave room for the probe.
Fail shape. "Smartest people, best training, client impact" as a paragraph. It fails the substitution test on contact.
Cluster 2 — Trajectory (who you are on paper)
These open half of all fit conversations. Not autobiography: a thread that makes the later behavioral story land.
| Prompt you hear | What it is scoring | Probe that usually follows |
|---|---|---|
| Walk me through your resume | One coherent arc, not CV karaoke | They pick a line and dig: "What did you own on that project?" |
| Tell me about yourself | Same arc in spoken form; usually 60–90 seconds | "Why consulting now?" bridges into Cluster 1 |
| What are you most proud of on this page? | Judgment about impact, not prestige | "What would you do differently?" |
| What feedback have you heard twice? | Self-awareness without self-flagellation | "Give me the last time that showed up at work" |
Pass shape. Three beats: where you started, two moments that built the skill this job uses, why this interview. End forward. Do not consume the PEI-depth story in the walk-through; you will need it later.
Fail shape. Chronology with no point, or a two-minute speech that leaves no oxygen for questions.
Cluster 3 — Past behavior (the stories that fill the sheet)
Firm language diverges; the underlying scores overlap. McKinsey runs a dedicated PEI and asks for two personal examples per published theme. BCG's recruiting brochure describes themes such as team contribution, achievements, independence, and learning. Deloitte publishes sample prompts next to recruiter intent: priorities, initiative, conflict, ambiguity.
| Prompt family | McKinsey-side score target | BCG / Bain flavor | Deloitte-side score target | Probe to prep |
|---|---|---|---|---|
| Changed someone's mind / disagreement | Personal impact / connection | Influence without authority | Conflict with a teammate; how you lead and work with others | "What did they say next?" "What did you change in your approach?" |
| Led a team through a hard call | Inclusive leadership | Team contribution under pressure | Lead a project or team; outcome | "Who resisted?" "What did you personally do, not the team?" |
| Built something with little guidance | Entrepreneurial drive | Independence / initiative | Saw a problem and took initiative | "What did you cut?" "What failed first?" |
| Adapted under a real constraint | Change / growth themes | Learning experience | Adapt to significant change; rush project with incomplete info | "What did you not know?" "When did you ask for help?" |
| Juggled priorities / missed something | Judgment under load | Maturity and energy | Balancing responsibilities | "What did you drop?" "Who did you disappoint?" |
For the long-form craft of one story told three firm lengths, use the behavioral interview pillar. For McKinsey's 10–20 minute probe format, leave this page for the PEI guide.
Two fully worked spoken answers
Invented candidate, same facts both times. Use the structure, not the biography.
Answer A — "Why Bain Dallas?" (motivation cluster)
Score target. Bain's published ask: explain why you want them specifically. Secondary: office constraint that survives "would you take New York?"
Spoken (~55 seconds).
"I will be in Dallas either way. My partner starts a three-year residency at UT Southwestern this July, and we already hold a lease near campus. That is not a preference; it is a constraint. I am targeting Bain Dallas because the staffing conversations I had with two Associates in March pointed to health systems and PE diligence on Texas industrials as the default mix for first-years who stay local. That is the work I want, and the local staffing model makes it more likely than a New York financial-services default. If I were location-flexible I would still rank Dallas first for that mix. The trade I already accepted is less PE brand-name on the street; the gain is the case mix and the life. I am not going to pretend a New York offer is equivalent."
Probe they should survive. "Would you take McKinsey Dallas if it came first?" Honest answer: firm-specific reasons still have to differ (training model, case ownership, people you met). Geography alone is not a firm answer.
Answer B — "Tell me about a time you changed someone's mind" (past-behavior cluster)
Score target. McKinsey-style personal impact; Deloitte's "conflict with a team member / how you lead and work with others"; BCG influence without authority.
Spoken opener (~90 seconds), then hold for probes.
"Last spring I was analytics lead on a pricing pilot for a regional grocery chain, eight stores. Our store ops director wanted to keep a weekend BOGO on private-label pasta because traffic looked strong. Eight weeks of basket data said it pulled low-margin volume and crowded out higher-margin sides. He disagreed in the Monday stand-up and said cutting it would kill weekend traffic.
I did not argue the model in the room. I asked for two hours with him and the category manager that afternoon, with three pages: traffic by hour for promoted versus non-promoted weekends, contribution margin per basket, and a two-store test that kept the BOGO in two controls. He still disliked the recommendation but agreed the traffic fear was untested. We ran the cut for three weekends. Traffic dipped 2 percent; contribution margin per basket rose 6 percent. He walked the result into the commercial meeting himself; we rolled the cut to the other six stores the next month.
What I owned was stopping the debate and designing a test he could live with. The commercial final call stayed with him."
Probes to rehearse out loud. "What exactly did he say when you first disagreed?" "What if the test had failed?" "Who else was in the room?" If you invent detail to answer those, the story is not ready. McKinsey asks for challenge detail and specific actions, with two examples per theme.
A scoring heuristic you can run on yourself
Score a recorded answer on three binary checks. Pass needs three yeses.
| Check | Yes | No |
|---|---|---|
| Substitution | Firm or office detail dies if you swap logos or cities | Generic "best people / best training" |
| Agency | You name what you did in first person | "We decided" with no personal move |
| Probe depth | You can answer "what happened next?" with a concrete beat | Story ends at the happy result |
In a typical first-round slate of eight, I estimate two or three candidates clear all three. The rest leak on the follow-up, not the opener. That range is my estimate from scoring rooms, not a published firm statistic.
Practice this week
Pick six prompts: two from each cluster. Record each answer once, then answer only the probe column for five minutes without restarting. That second pass is the real rehearsal.
For PEI-depth stories with four follow-ups, use CoachNed's behavioral simulator. Everything is open for seven days with no card; then $120 for a recruiting season or $49 a month. Length craft: behavioral interview guide.
Frequently asked questions
Are consulting fit questions the same as McKinsey PEI?
No. Fit usually means motivation plus short past-behavior prompts at BCG, Bain, and Big Four. McKinsey PEI is a longer probe of one experience against published themes. Prepare both; do not burn a PEI story on a 60-second why-firm.
How many fit stories do I need?
Enough to cover Cluster 3 without repeating in one round. McKinsey suggests two examples per PEI theme. For BCG, Bain, and Deloitte, six to eight drilled stories usually cover the families above if each can take a probe.
Should I memorize different why-firm answers for every logo?
Yes on the specific fact (person, practice, staffing, published principle). No on inventing a new personality. If the paragraph survives a logo swap, rewrite it.
What does Deloitte mean by using STAR?
Deloitte recommends Situation, Task, Action, Result so answers stay clear and timed. Situation and Task stay short; Action carries the score; Result closes with a number or a changed decision. Container, not script.
Can I use the same conflict story at McKinsey and Bain?
Often yes on the facts. Adjust length: McKinsey may sit in the disagreement for 10–20 minutes; Bain or BCG may take two minutes and move to the case. Prep the probes, then trim.
Sources
- Interviewing at McKinsey — PEI format; prepare detailed personal examples across published themes. Checked 2026-09-24.
- BCG consulting interview process — skills interview on experience, skills, and motivation; values and core competencies. Checked 2026-09-24.
- BCG Recruiting Interview Preparation Brochure (Nov 2018) — personal discussion themes (team, achievement, independence, learning) and fit signals. Checked 2026-09-24.
- Bain interviewing — curiosity and entrepreneurial bent; explain why Bain specifically; behavioral questions on past challenges. Checked 2026-09-24.
- Deloitte behavioral interview tips — STAR; achievement, communication, leadership and teaming, aptitude; sample prompts with recruiter intent. Checked 2026-09-24.
CoachNed is independent practice material and is not affiliated with McKinsey, BCG, Bain, Deloitte, or any firm named above.