What Is MBB Consulting? McKinsey, BCG and Bain

MBB means McKinsey & Company, Boston Consulting Group (BCG), and Bain & Company. These three global firms are often grouped as the Big Three because of their strategy heritage, client reach, recruiting presence, and influence on the consulting industry.

The acronym does not mean the firms only write strategy recommendations. Their public capability pages describe work across transformation, operations, organization, technology, analytics, implementation, and other specialist areas. What you do depends on the office, practice, role, and project.

MBB at a glance

These are starting points, not personality labels. Claims such as “McKinsey is formal,” “BCG is intellectual,” or “Bain is social” are too broad to choose an employer. Talk with people in the office and role you would actually join.

What do McKinsey, BCG, and Bain actually do?

MBB teams help organizations make and execute consequential decisions. Public firm materials show overlapping portfolios, including:

Not every office offers every capability at the same scale. Read the role description and practice pages rather than relying on the MBB label.

How are the three firms different?

The safest comparison is based on observable choices:

Compensation can matter, but public figures become stale and offers differ by geography, level, and year. Compare the written offers you actually receive. The consulting salary report can provide market context without pretending one number covers every candidate.

MBB versus Big Four and other firms

MBB is one segment of a much larger consulting market. Big Four firms, strategy specialists, operations firms, technology consultancies, and boutiques may offer work that better matches a candidate's desired industry, location, or delivery model.

“Better” is therefore a role-level decision, not a universal firm ranking.

Who does MBB hire?

The firms recruit students, advanced-degree candidates, MBAs, and experienced professionals, but available entry points vary. Common paths include:

• Undergraduate or master's internships and full-time generalist roles.
• MBA internships and post-MBA roles.
• Advanced-degree programs for PhD, medical, law, and other candidates where offered.
• Experienced-hire and specialist roles in industry, analytics, technology, design, implementation, and functions.

Eligibility language and dates can change. Verify them on the current posting and do not apply based on a previous cycle's calendar.

What is the MBB interview process?

An MBB process may include application screening, an online or digital assessment, case interviews, and behavioral or experience questions. The sequence and count vary by firm, role, office, and recruiting channel.

Do not assume every McKinsey case is interviewer-led or every BCG and Bain case is candidate-led. Interviewers can vary the degree of guidance, and special roles can use different formats.

How should you order MBB applications and interviews?

Apply wherever the role fits; do not submit to one firm only because an acronym grouped three firms together. If you can influence scheduling, use this order:

1. Protect every official deadline and assessment window.
2. Avoid preventable collisions between interviews.
3. Leave a small amount of time between processes to apply lessons.
4. Do not intentionally use a firm you would accept as a disposable mock interview.
5. If offers overlap, compare the actual office, role, people, and terms.

Before the first interview, test your reasoning in a realistic case, then train the skill that the attempt exposed rather than chasing a universal case count. Start with the GreenBite guided case. If the process is still unfamiliar, review the case interview lesson before the next attempt.

How do you choose among McKinsey, BCG, and Bain?

Score the options only after gathering role-level evidence:

MBB is useful shorthand. It is not a substitute for choosing the actual job.

Sources

• McKinsey: capabilities
• McKinsey: interviewing
• BCG: capabilities
• BCG: careers
• Bain: industries and capabilities
• Bain: hiring process