Twitter CEO and co-founder Evan Williams has announced that he is stepping back from the role to focus purely on product strategy.
His replacement is current COO Dick Costolo, who for most of the last year has been focusing on Twitter's monetisation efforts.
"I am most satisfied while pushing product direction," Williams wrote in a blog post.
"Building things is my passion, and I’ve never been more excited or optimistic about what we have to build... Starting today, I’ll be completely focused on product strategy."
Twitter currently has 165 million registered users creating 90 million tweets every day.