The 10 Biggest Consulting Firms in the World (And Why They Matter)
Curious about the heavyweights shaping global business strategies and transformations? Let’s dive into the top ten consulting firms dominating the industry—exploring their roots, reach, and organizational models.
1. McKinsey & Company — mckinsey.com
Founded: 1926 in Chicago by James O. McKinsey; expanded under Marvin Bower
Today: ~45,000 consultants, US$16 billion in revenue, 130+ offices globally
Structure: Matrix organization with strategy, operations, digital, and sector practices
2. Boston Consulting Group (BCG) — bcg.com
Founded: 1963 by Bruce Henderson in Boston
Today: ~33,000 staff, US$13.5 billion revenue in 2024, 100+ offices
Structure: “Pod” model—multi-functional teams focused on proprietary frameworks like the BCG Matrix
3. Bain & Company — bain.com
Founded: 1973 in Boston by Bill Bain (ex-BCG)
Today: ~15,000 employees, US$5.8 billion revenue, 65 offices
Structure: Partner-led, collaborative culture centered on implementing strategy and serving private equity
4. Accenture — accenture.com
Founded: Evolved from Andersen Consulting in the 1950s; rebranded in 2001
Today: ~700,000 employees, US$60+ billion in revenue, global reach
Structure: Multi-practice model encompassing strategy, tech, digital transformation, outsourcing
5. Deloitte Consulting — deloitte.com
Origins: Consultancy division of Deloitte & Touche, consolidated in mid-1990s
Today: ~460,000 professionals (Big Four total) generating US$67 billion+
Structure: Divided into strategy, human capital, tech, risk—part of a global advisory network
6. PwC (PricewaterhouseCoopers) — pwc.com
Founded: Merger of Price Waterhouse & Coopers & Lybrand in 1998
Today: ~328,000 staff (Big Four total)
Structure: Offers audit, tax, and advisory services; consulting teams embedded in global network
7. EY (Ernst & Young) — ey.com
Founded: Through numerous mergers in the Big Four lineage
Today: ~365,000 professionals worldwide
Structure: Four service pillars—assurance, transactions, consulting, strategy within EY network
8. KPMG — kpmg.com
Founded: Through 1987 merger (Klynveld Main Goerdeler)
Today: ~227,000 staff globally
Structure: Begins with accounting and tax foundations, supported by strong advisory and consulting functions
9. Arthur D. Little — adlittle.com
Founded: 1886 in Boston by MIT chemist Arthur Dehon Little
Today: ~1,300 consultants in 40+ offices (est.)
Structure: Focus on R&D, innovation, and digital transformation; partnership model rooted in scientific rigor
10. L.E.K. Consulting — lek.com
Founded: 1983 by former Bain partners in Boston and London
Today: ~2,100 staff across 21 global offices; US$800 million revenue
Structure: Strategy boutique with strengths in private equity, M&A, growth strategy, marketing execution
Why These Firms Matter
- McKinsey, BCG, and Bain (MBB) set the gold standard for strategy work.
- Accenture and the Big Four bring tech integration, global scale, and full-service advisory.
- Arthur D. Little and L.E.K. offer nimble, specialized expertise—perfect examples of boutique consulting power.
Each model offers lessons on leadership structures, scalability, brand positioning, and client value.
To close…
Whether you’re building your own consultancy or looking to understand how major players operate, studying these firms offers invaluable insight.
From McKinsey’s strategic thinking, BCG’s frameworks, Accenture’s tech solutions, to Arthur D. Little’s innovation focus—there’s a model to learn from.
