This article, based on a recent InfoCom study detailing over 30 countries, looks at enterprise telephony markets worldwide. We analysed the enterprise telephony as PBX (Private Branch eXchange) and IPT (IP Telephony) solutions for systems with over 400 lines. We therefore clearly excluded the SMB (Small and Medium Businesses) sector. The article starts by looking at the size of this segment by regions and main countries and then highlights country differences regarding the share of IP, replacement rates and the take up of VM (Voice Mail) and UM (Unified Messaging) functions. Finally, we present vendors market shares, focusing on Avaya and Cisco but also highlighting the ongoing prevalence of local champions. All figures relate to extension lines shipments in the 6 months to March 2011.