Dick Costolo is the current CEO of Twitter and was its former COO. He took over as CEO from Evan Williams in October 2010.

Costolo graduated in 1985 with a B.S. degree in computer and communication sciences, from the University of Michigan, where he was also a brother in the Phi Gamma Delta social fraternity. Costolo became involved in theater during his senior year at the University of Michigan, when he began taking theater classes to fulfill the university's graduation requirements. Upon graduation, he decided not to accept offers from technology companies and instead moved to Chicago to work in improvisational comedy.

After his improv career in Chicago, Costolo was at Andersen Consulting for 8 years, where he was a senior manager in product and technology groups. He then co-founded Burning Door Networked Media, a web design and development consulting company, which was acquired by Digital Knowledge Assets in October 1996. He then went on to co-found SpyOnIt, a web page monitoring service, which was sold in September 2000.

In 2004, Costolo, along with Eric Lunt, Steve Olechowski, and Matt Shobe, founded the web feed management provider FeedBurner. After Google bought FeedBurner in 2007, Dick Costolo became an employee of the search giant. After the acquisition, Costolo began working in other areas of Google. In July 2009, he left Google, and in September 2009, it was announced that he was joining Twitter as its COO. Although his 2010 takeover as CEO was supposed to be temporary, while CEO Evan Williams was on paternity leave, it eventually became a permanent position.

In May 2011, it was announced that President Obama had appointed Costolo to the National Security Telecommunications Advisory Committee, along with the Corporate Vice President of Microsoft’s Trustworthy Computing Group, Scott Charney, and McAfee President of Security David DeWalt.

Among his many accolades, in 2013, Business Insider referred to him as "one of Silicon Valley's most impressive CEOs," he was named CEO of the year at 2013’s Crunchies Awards and TIME Magazine named him one of the 10 Most Influential U.S. Tech CEOs.