This paper addresses the problem of broadcasting video over wireless channels. In such a scenario, different end users perceive the video signal through channels with different quality. We propose a source-channel coding system, that partitions the video data in such a way that maintains a baseline quality of service even for the user with the worst channel. The system consists of a layered source representation that is robust to error propagation effects, combined with a multilevel channel coding scheme that provides an unequal error protection to the different layers of the encoded video. Experimental results show that our system is robust and guarantees a baseline quality of service to all users over a wide range of channel conditions.