Avaya Inc. /əˈvaɪ.ə/ is a privately held computer networking, information technology and telecommunications company that is a global provider of business communications systems. The international headquarters is in Basking Ridge, New Jersey, United States. The company provides contact centers, networking (routers, switches and other networking hardware), unified communications, and video products (integrated hardware and software) solutions and services.

In July and August 2000 interviews reported that Avaya Communications would be created on 1 October 2000 when the unified communications and call center businesses left Lucent Technologies Inc. or Lucent enterprises. The spun off of Avaya with 34,000 employees also received $400 million in capital from Warburg Pincus.Henry Schacht became the board chairman and the first CEO was Don Peterson who was promoted from the CFO position of Lucent. Avaya had a stock symbol of "AV" and debuted at $20 a share. Since 2001, the company has sold, and acquired several companies to support its current product set – Vista, VPNet. Quintus, Routescience, Nimcat Networks, Spectel, Ubiquity Software, and Traverse Networks. Sales through channels have grown from 98% direct to 50% alternative channels. In 2003 Avaya sold its cabling unit to CommScope for $263 million to focus on its phone gear and services businesses. In 2004 Avaya expanded in Europe through a $370 million acquisition of Tenovis and in Asia through a majority interest in Tata Telecom (now Avaya Global Connect). In 2006 Louis D'Ambrosio took over as the CEO and president of Avaya. and on 12 Jan 2007 they announced the acquisition of Ubiquity Software Corporation for $144 million. Ubiquity develops SIP end-user applications.