Avaya is an American multinational technology company headquartered in Santa Clara, California that specialises in business communications, specifically unified communications (UC), contact centre (CC), and services. Serving organisations at 220,000 customer locations worldwide, Avaya is the largest pure- play UC and CC company, ranking No. 1 in CC and No. 2 in UC and collaboration. Avaya was spun off as its own entity from Lucent Technologies in 2000. It remained a public company from 2000 to 2007, when it was purchased by private equity firms. On December 15, 2017, it again became a publicly- listed company, trading under the stock ticker AVYA.