Mobile Collaborative Video Production - We invent and investigate mobile collaborative live video mixing. A first generation of applications, in this genre, make it possible to broad cast live video streams from various types of use contexts over mobile networks such as 3G ( see for example bambuser.com and qik.com). We explore a second generation of such applications, where professional techniques for collaborative live video editing are made available on mobile platforms. Using networked camera phones, we show how it is possible to mix live concurrent video streams from multiple users for public display on internet and locally. The design space includes adapting these new possibilities, previously only available to professional TV-production teams, to amateurs in various contexts of use. Such situations might include the broadcast of multiple live images of soccer matches by parent or, as demonstrated by the Instant Broadcasting System, to visitors at night clubs, and to visitors of public exhibitions.