Instances of the conversation class are obtained from the conversations manager. This class exposes methods allowing you to get and set conversation properties, merge one active conversation with other active conversations, add or remove collaboration modalities, and terminate the active conversation represented by an instance of Conversation .

The conversation dialog streams are encapsulated by Microsoft.Lync.Model.Conversation . . :: . . InstantMessageModality and Microsoft.Lync.Model.Conversation.AudioVideo . . :: . . AVModality . Each of these modalities carries its own set of properties and events for the specific characteristics of each modality. Using the Microsoft.Lync.Model.Conversation.AudioVideo . . :: . . AVModality , you can hold, forward, or transfer an audio conversation.

The people who participate in a conversation are encapsulated by instances of the Participant class. If you add more than two participants to a conversation, the conversation is automatically transformed into a conference which other users can join without an invitation as long as the conference entry policy does not prohibit it.

The conferencing feature of the Conversation is implemented simply by adding a third participant to a conversation. You can change the default conference properties by setting any of a small number of conversation properties accessed using the ConversationProperty enumeration on Properties