Big Three (management consultancies)

The Big Three or MBB refers to the name colloquially given to the world's three largest strategy consulting firms by revenue. They are also considered to be the most prestigious employers in the management consulting industry.McKinsey is the biggest of these with an annual revenue of $8.4bn followed by BCG ($5.6bn revenue) and then Bain & Company ($2.3bn revenue). Considering significant disruption of the industry and the slowing growth of the Big Three, the firms face increasing competition from younger, more agile competitors such as L.E.K. Consulting and Oliver Wyman.

The three consulting firms widely regarded as constituting the Big Three or MBB are McKinsey & Company, Boston Consulting Group and Bain & Company.

This firm was founded under the name "McKinsey & Company" in Chicago by James McKinsey in 1926. The firm has grown significantly since then, establishing 104 offices located in 60 different countries as of 2014.McKinsey & Company has been voted number one in the "The Best Consulting Firms: Prestige" list of the Vault.com career intelligence website consecutively for 14 years since the year 2002. The firm currently serves two-thirds of the Fortune 1000. Their areas of expertise include management, organisation, operations and IT.

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