Top 20 Business Schools in the world:
According to the Financial Times MBA Survey of top 100 business schools 2016, Insead was rated as the No. 1 MBA provider in the world:
1. Insead 2. Harvard Business School 3. London Business School 4. University of Pennsylvania: Wharton 5. Stanford 6. Columbia Business School 7. University of California at Berkeley: Haas 8. University of Chicago: Booth 9. MIT: Sloan 10. University of Cambridge 11. Northwestern University: Kellogg 12. IE Business School 13. IMD 14. HKUST Business School 15. HEC Paris 16. Iese Business School 17. Ceibs 18. Yale School of Management 19. New York University: Stern 20. University of Michigan: Ross

Top 20 US Business Schools as ranked by U.S. News & World Report (2014):
1. Stanford University 1. Harvard University 3. University of Pennsylvania (Wharton) 4. MIT (Sloan) 4. Northwestern University (Kellogg) 6. University of Chicago (Booth) 7. UC Berkeley (Haas) 8. Columbia University 9. Dartmouth College (Tuck) 10. New York University (Stern) 11. Duke University (Fuqua) 12. University of Virginia (Darden) 13. Yale University 14. UCLA (Anderson) 14. University of Michigan--Ann Arbor (Ross) 16. Cornell University (Johnson) 17. University of Texas--Austin (McCombs) 18. Emory University (Goizueta) 19. Carnegie Mellon University (Tepper) 20. University of North Carolina--Chapel Hill (Kenan-Flagler)

Top 20 B-Schools in Europe:
According to the Economic Intelligence Unit 2009 rankings of full time MBA providers, IESE tops the list of European b-schools:
1 IESE Business School - University of Navarra (Spain) 2 IMD (Switzerland) 3 London Business School (Britain) 4 Vlerick Leuven Gent Management School (Belgium) 5 Cambridge Judge Business School (Britain) 6 HEC School of Management, Paris (France) 7 IE Business School (Spain) 8 Cranfield School of Management (Britain) 9 Henley Business School (Britain) 10 Warwick Business School (Britain) 11 INSEAD (France / Singapore) 12 Mannheim Business School (Germany) 13 ESADE Business School (Spain) 14 Ashridge (Britain) 15 University College Dublin - Michael Smurfit Graduate School of Business (Ireland) 16 Rotterdam School of Management, Erasmus University (Netherlands) 17 International University of Monaco (Monaco) 18 Oxford Said Business School (Britain) 19 Durham Business School (Britain) 20 Manchester Business School (Britain)

Top 20 B-Schools in India by Outlook Survey (2008):
1. IIMA 2. Xavier Labour Relations Inst Jamshedpur 3. IIML 4. IIM Indore 5. National Inst of Industrial Engg Mumbai 6. Faculty of Management Studies Delhi 7. SP Jain Inst of Management Mumbai 8. Xavier Institute of Management Bhubaneshwar 9. Indian Institute of Foreign Trade Delhi 10. Inst of management Technology Ghaziabad 11. Management Development Inst Gurgaon 12. Shailesh J. Mehta School of Mgmt Mumbai 13. International Mgmt Institute Delhi 14. Jamnalal Bajaj Inst of Mgmt Mumbai 15. Narsee Monjee Institute of Mgmt Mumbai 16. Welingkar Inst of Management Mumbai 17. Symbiosis Centre for Mgmt Pune 18. Institute of Rural Management Anand 19. KJ Somaiya Inst of Mgmt Mumbai 20. Alliance Business Academy Bangalore

* Suggested Reading:

Top 10 Business Schools

Top Business Schools in US

Top 10 Online MBA Schools

World University Ranking Tables

America - US News & World Report, The Princeton Review, BusinessWeek
Canada - Maclean's, Gourman Report Ranking of Canadian Universities
UK - Sunday Times, Guardian, Times Good University Guide, Daily Telegraph
World - Shanghai Jiao Tong ARWU Rankings, Webometrics, Newsweek