CallManager is a Cisco product. It is formally referred to as Cisco CallManager (note capitalization), or CCM for short.

CallManager tracks all active VoIP network components; these include phones, gateways, conference bridges, transcoding resources, voiceboxes and others. The software keeps track of every phone's status, is the master-end of the SCCP, passing commands to the MGCP controlled devices.

CCM evaluates called numbers and activates gateway events to receive or send calls to the PSTN.

The Cisco CallManager is installed on the Cisco Media Convergence Server (MCS). Typically, multiple (up to five) MCS are clustered for distributed call processing and fault tolerance.

The latest version to be released (2004) is Cisco CallManager 4.1. It includes various enhancements such as handling of multiple calls (up to 200) on a single line presence. Additionally, some of the new features of CCM 4.0 include greatly enhanced conference calling features, enhanced Client Matter Code (CMC) and Forced Account Code (FAC), Multilevel Precedence and Preemption (MLPP) and Malicious Call Identification (MCID).