Here given below is the listing of Top Outsourcing Companies in World according to the rankings

ISS
Accenture
CBRE
Kelly Outsourcing and Consulting Group
Colliers International
HCL Technologies
NCR Services
Pactera
Capgemini
CGI
Cassidy Turley
Firstsource
transcosmos
Sitel
Sykes Enterprises
Jones Lang LaSalle
Serco Global Services
Luxoft
Johnson Controls – Global Work Place Solutions
Newmark Grubb Knight Frank
Towers Watson
L&T Infotech
LeasePlan USA
Insigma
IBA Group
SoftServe
Quatrro
Infotech Enterprises
EXL
Swiss Post Solutions
TIVIT
Wicresoft
Mindtree
Cybage Software
Aegis
Sutherland Global Services
Softtek
MAYKOR
Datamatics Global Services
Xchanging
Aon Hewitt
Aptara
Canon Business Process Services
Concentrix
iSoftStone
tgestiona
CIeNET International
SPi Global
Neusoft
Diebold Integrated Services©
HGS
EPAM Systems
WNS Global Services
Unisys
Indecomm Global Services
MphasiS, an HP Company
Stefanini
FPT Software
ChinaSoft International
CPA Global Group
Altisource
Donlen
Syntel
TELUS International
ITC Infotech
TeleTech
RR Donnelley Global Outsourcing
MERA
NEORIS
Brookfield Global Relocation Services
The Results Companies
Persistent Systems
Mastek
Emerio GlobeSoft
Aditya Birla Minacs
Inspur
ARAMARK
Ness Technologies
Itransition
TEAM International Services
Intetics
Miratech
Softengi
ReSource Pro
Prominente
Oxagile
Bleum
LegalBase
Auriga
ServicEngineBPO
Harbinger Systems
Ajuba international
Reksoft
DATROSE
Clutch Group
QX
GP Solutions
SaM Solutions
CrysTelCall
AGS Health