—Layered streaming is an effective solution to address the receiver heterogeneity in peer-to-peer (P2P) multimedia distribution. This paper targets a fundamental challenge in this application, i.e., how to find optimal routing structure maximizing receiver throughput and achieving intra-layer and inter-layer fairness. We formulate the problem using the multicommodity flow theory, and propose a series of routing algorithms that fully explore the tradeoff between theoretical optimality and practicability. For each algorithm, we have proved its optimality to achieve maximum throughput under fairness constraint, or approximation bound to the optimal rate. Experimental results confirm our algorithms to greatly outperform their theoretical bounds.