The ISG Index™ provides a quarterly review of the state of the Global IT Services Market, covering both the traditional sourcing market and the fast-growing as-a-service (Infrastructure-as-a-Service and Software-as-a-Service) market. We cover data and trends for clients, service providers, analysts and the media. For more than a decade, it has been the authoritative source for marketplace intelligence related to outsourcing transaction structures and terms, industry adoption, geographic prevalence and service provider performance.