Terms of the acquisition were not disclosed. The deal comes just 14 months after the first public demo of CoTweet, which has since gone on to attract major brands as clients, including Coca-Cola, Ford, McDonald’s and Starbucks.

CoTweet’s Twitter management platform is designed to allow companies to manage and monitor their corporate accounts and customer relationships, and on top of this adds a variety of analytics tools to measure the reach of Twitter messages and their click-through rates, the level of follower engagement and the influence of particular brands and users.

Post-acquisition the company will continue to operate out of San Francisco as a business unit of ExactTarget. Meanwhile, CoTweet co-founder and CEO Jesse Engle (pictured) will set up a social media lab for the parent company.

Engle said: “We see a huge opportunity to build on ExactTarget’s incredible business and customer relationships to help companies drive more measurable value from social media. As part of ExactTarget, we’ll have the global resources to cement our early lead, rapidly expand our platform and develop the next generation of social media communication tools.”