In addition to Microsoft Teams, AVOXI's VoIP service works with virtually any phone system setup.  For more information, see how to configure SIP trunks. Options for system-specific configuration instructions are included at the bottom, including:  3CX SIP Trunk Configuration FreePBX SIP Trunk Configuration Twilio SIP Trunk Configuration Asterisk SIP Trunk Configuration Five9 SIP Trunk Configuration Talkdesk SIP Trunk Configuration Genesys SIP Trunk Configuration