RadiumOne, an online advertisement company that leverages social media for better advertising performance, closed a $21 million Series B funding. The funding was led by Crosslink Capital, other investors include DFJ Esprit, and previous investors Adams Street Partners and Trinity Ventures. The company is planning to use this funding for international expansion and acquisitions. It recently opened its UK office, and in the coming months will be launching in continental Europe and Asia Pacific.

“Our goal at RadiumOne is to use social data to change online advertising for the better, and make a positive measureable impact on advertisers and consumers,” says Gurbaksh Chahal, Founder and CEO, RadiumOne. “The ‘social evolution of the Internet has given us an opportunity to do this, and we feel we are filling the void of socially-targeted advertising outside of Facebook. This latest round of funding will accelerate our growth, and allow us to make the moves that will truly establish RadiumOne as the pioneer in bringing social advertising to the open web,” adds Chahal.

Since its inception 18 months ago, RadiumOne has worked with over 200 Fortune 500 brands. “When we look at potential portfolio companies, we try to identify who has the technology and vision to really disrupt an industry and make a global impact,” says Jim McLean, partner at Crosslink Capital and new member of RadiumOne’s board. “We have seen it firsthand with companies like Pandora, and we know that RadiumOne will be extending that same disruption into the display advertising ecosystem,” says McLean. This round brings the total funding raised by the company to $33.5 million.