This xDRD (Excel-based Data-Rich Deliverable) is part of the Business IP and Business Networks subscription and falls within the IMS market. This forecasts discusses and analyzes US carrier IMS infrastructure and equipment investment spending from 2006-2011. IMS or IP Multimedia Subsystems includes all IMS-related investments by providers and vendors. The IP Multimedia Subsystem (IMS) is a standardized Next Generation Networking (NGN) architecture for telecom operators that want to provide mobile and fixed multimedia services. It uses a Voice-over-IP (VoIP) implementation based on a 3GPP standardized implementation of SIP, and runs over the standard Internet Protocol (IP). Existing phone systems (both packet-switched and circuit-switched) are supported. The Expert Guide for this DRD is Kneko Burney.