Five9 Inc., the leading provider of cloud-based contact center software, has announced the successful completion of an additional round of equity financing, raising $12 million. The additional funding follows record revenue growth in 2011 for Five9, exceeding 70 percent growth over 2010 revenues. With approximately 360 employees, including the largest engineering team in the cloud contact center market, Five9 is focused on revolutionizing the call center industry, as evidenced by its exceptional customer success and remarkable growth trajectory.

The latest financing round was led by Adams Street Partners with Hummer Winblad Venture Capital and Partech International also participating. In total, Five9 has raised more than $49 million in funding.

"Five9 ended 2011 as the clear leader in the cloud contact center space, with more customers and faster revenue growth than any other provider in the market," said Five9 CEO Mike Burkland. "Demand for cloud-based contact center software is accelerating as customers realize the significant benefits: lower costs, improved productivity and streamlined operations. The additional funding positions us well to take full advantage of our momentum, and gives us an opportunity to expand our current leadership position."

"Five9 is well positioned as the strongest solution for enterprises looking to replace legacy on-premise Cisco, Avaya and Genesys systems," said David Welsh, partner, Adams Street Partners. "The company has demonstrated tremendous technical capability, combined with prudent financial management, through periods of high revenue growth and increasing market share. We are excited to partner with Five9 as enterprises increasingly turn to cloud-based contact center solutions."

Five9 is revolutionizing contact centers the way that Salesforce.com revolutionized customer relationship management. Processing more than two billion customer calls per year, for more than 1,500 customers worldwide, the Five9 Virtual Contact Center is the leading cloud-based contact center software on the market. In 2011, Five9 was named to Inc. Magazine's list of America's fastest-growing private companies for the second year in a row and also was named to the San Francisco Business Times' list of largest software companies in the San Francisco Bay Area.

The company gives enterprises of all sizes access to sophisticated and innovative contact center solutions quickly, at a cost of ownership far lower than traditional premise-based solutions. For more information on Five9, please visit www.five9.com or call 1-800-553-8159.

About Five9 Five9 is the leading global provider of cloud-based contact center software for sales, marketing and support. The award-winning Five9 Virtual Contact Center and Predictive Dialer serve customers of all sizes on five continents. Customers profit from Five9′s reliable, robust functionality that provides the best technology, improves agent productivity, and delivers business flexibility.

About Adams Street Partners Adams Street Partners, LLC is a leading private equity investment firm, providing primary and secondary partnership and direct investment management services to institutional clients. Adams Street Partners is one of the largest managers of private equity investments in the world and has one of the longest histories. Together with its predecessor organizations, Adams Street Partners has been investing in private equity partnerships since 1979 and managing direct investments in private equity since 1972. Adams Street Partners has offices in Chicago, London, Menlo Park, Beijing and Singapore.