McKinsey & Company

James O. McKinsey established the firm in Chicago during 1926 to apply scientific management principles to business challenges. The organization quickly grew beyond its initial accounting roots after Marvin Bower joined in 1933. Bower restructured the company into a professional service entity that prioritized client confidentiality and meritocracy over short-term partnership profits. This shift laid the groundwork for the firm's expansion into a global network spanning more than 130 cities across 65 countries.

The headquarters moved to New York City in the mid-20th century and remains there today. As a private partnership, the firm does not release public financial statements or valuation data. Industry estimates place annual revenue between $10 billion and $13 billion USD, derived primarily from high-value advisory services in corporate strategy, operations, and digital transformation.

Recent years have seen significant legal and political scrutiny. Prosecutors in France and Belgium seized approximately €65 million ($70 million USD) from the firm in September 2026 as part of an investigation into aggressive transfer pricing schemes. Earlier that same year, a GOP freshman politician targeted the company over alleged diversity, equity, and inclusion practices described as plainly illegal. [edit]