This paper uses a dynamic stochastic model to solve for the optimal pricing policy of music recordings in the presence of P2P file-sharing networks eroding their sales. We employ a policy iteration algorithm on a discretized state space to numerically compute the optimal pricing policy. The realistically calibrated model reflects the real-world figures we observe and provides estimates of the optimal pricing policy as well as comparative statics figures. The pricing policy is such that, for a given P2P network size, prices are increasing in the number of buyers of the product and, for a given number of buyers of the product, prices are non-monotonic in the P2P network size. Surprisingly, in the presence of P2P networks, increases in product...