Big Three (management Consultancies)

The Big Three or MBB refers to management consulting firms McKinsey & Company, Boston Consulting Group, and Bain & Company. Widely considered the most prestigious strategy consulting firms in the world, the three companies are distinguished by the depth and rigor of their analyses and recommendations, rich histories of service dating back to their foundings in the mid-19th century, and strong client bases spanning some of the world's largest and more important companies.

Known for their highly selective and competitive recruiting process, the MBB firms hire a large portion of their consultants from prestigious undergraduate universities and MBA programs around the world, supplementing them with more senior industry hires with deep expertise in specific sectors served by the firms. While continuing to maintain a focus on the strategy consulting work for which they originally rose to prominence, the MBB firms have expanded their portfolio of offerings over the years to include consulting services such as operating model design, performance improvement, M&A diligence, human capital, and digital / AI transformation.

Praised by many for the impactful results they have achieved with their clients, the MBB firms have also been the subject of criticism over the years for alleged unethical activities, with a prominent example being McKinsey's role in helping Purdue Pharma "turbo-charge" its sales of OxyContin, which has been cited as a direct contributor to the opioid epidemic in the United States.

The firms

McKinsey & Company, Boston Consulting Group, and Bain & Company, collectively referred to as "MBB", are widely considered the three top and most prestigious strategy consulting firms in the world. Jobs at these firms are among the most sought-after by MBA students and have a less than 1% acceptance rate.

These three firms are among the world's largest strategy consulting firms by revenue. Their latest publicly available data is summarized in the table below:

McKinsey & Company

McKinsey & Company was founded in Chicago by James O. McKinsey in 1926. The firm has grown significantly since then, establishing 104 offices located in 60 countries as of 2014.

Boston Consulting Group

BCG was founded in 1963 by Bruce D. Henderson, a former Arthur D. Little consultant and a Vanderbilt University and Harvard Business School alumnus. Starting out with only two consultants, the firm quickly grew. As of 2021, it employs 25,000 people in over 90 offices in more than 50 countries.

Bain & Company

Bain & Company was founded by Bill Bain in 1973 after leaving BCG. The firm pioneered private equity consulting and the fund Bain Capital was founded by partners from Bain & Company and led by Mitt Romney. According to the company's website in 2017, it had 65 offices in 40 countries. Bridgespan, a non-profit consultancy, was spun out of Bain in the early 2000s by three former Bain employees. Bain is widely known for its culture and was ranked #1 on Glassdoor's "Best Places to Work" list for 2025, a ranking it has frequently achieved since the list was first published.

See also

* Big Four accounting firms
* Corporate services
* List of management consulting firms

References

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International management consulting firms