Here is the whole list of Best outsourcing service suppliers as released by IAOP

1. IBM - Size and Growth

2. Cap Gemini - Customer Testimonials

3. Hewlett-Packard - Executive Leadership

4. Sodexho Alliance - Number of Centers/Locations

5. Accenture - Balanced Strength

6. Wipro Technologies - Balanced Strength

7. Infosys - Customer Testimonials

8. Genpact - Executive Leadership

9. Tech Mahindra - Employee Management

10. Cambridge - Executive Leadership

11. Mastek - Methodologies/Innovation

12. CGI Group - Number of Centers/Locations

13. Xchanging - Size and Growth

14. EDS - Methodologies/Innovation

15. HCL Technologies - Methodologies/Innovation

16. ARAMARK - Number of Centers/Locations

17. ACS - Number of Centers/Locations

18. Teletech - Balanced Strength

19. Colliers International - Size and Growth

20. Cognizant - Number of Centers/Locations

21. Unisys - Balanced strength

22. EMCOR - Number of Centers/Locations

23. ClientLogic - Balanced Strength

24. LASON - Balanced Strength

25. Neusoft - Employee Management