Amocs is a provider of software and services for billing, customer relationship management (CRM), and business and operations support systems (OSS). Its traditional clients are telecommunications "Tier-1" and "Tier-2" providers such as AT&T Mobility, Cable One, Cablevision, Comcast, DirecTV, Jupiter Communications, Sprint-Nextel, T-Mobile, Sensis, Vodafone, Fido Soltuions and Rogers Communications (both of which use the ICM/CRM application). The company also offers outsourced customer service and data center operations. Headquartered in Chesterfield, Missouri, Amdocs has more than 17,000 employees and serves customers in more than fifty countries.