Twitch.tv is one of the most successful online live streaming platforms in the world, with 200 million viewers, 2 million regular "streamers," and a market value of over $1billion. In this paper, we offer a first conceptualization of streamers as social media influencers, and how effectively they can perform strategic communication for sponsors. We draw on extensive ethnographic research and over a hundred semi-structured interviews with streamers to address two questions: first, how does Twitch operate as a platform for strategic communication; second, what skills do streamers need to be successful influencers? In the first case, we show Twitch is well suited to influencing, in large part due to its integration of data analytics, while streamers are using these tools to adopt a business-oriented mindset; in the second case, we show the importance of authenticity to both streamers and clients, and how channels of different sizes offer strategic communication opportunities. The article contributes to the emerging literature on Twitch, developing insights from influencing and strategic communication, but given the increasing scope of live streaming, we also argue the phenomenon - particularly when combined with the economic dynamics of influencing - is just as important for making sense of the wider media landscape today.