The Microsoft Unified Communications Managed API 2.0 Core SDK is a managed-code platform that provides access to and control over instant messaging, telephony, audio/video conferencing, and presence. It is intended to support the development of middle-tier applications targeting Microsoft Office Communicator and Microsoft Office Communications Server 2007 R2.

The UCMA 2.0 Core SDK abstracts away most of the Office Communications Server protocols by offering an API that exposes almost all of the features of the protocol, but is simpler to understand and use. For example, the contacts and groups for a user can be consumed using the ContactGroupServicesclass. A conference can be scheduled using the ConferenceServicesclass. A user or application can initiate a conversation with other users or applications using the Conversationclass. An application can subscribe to the presence of other users or applications using the LocalOwnerPresenceand RemotePresenceclasses.

The Unified Communications Managed API 2.0 Core SDK is based on Unified Communications Managed API V1.0.