Inter-cell interference coming from multiple base stations (BS) in adjacent cells limits the capacity of wireless cellular networks. In this paper, we exploit the uplink-downlink duality principle and BS cooperation to design linear and nonlinear downlink inter-cell interference management techniques for multi-user multiple-input-multiple-output (MIMO) systems. The proposed linear algorithm can effectively effectively eliminate the inter-cell interference and achieves bit-error-rate (BER) fairness among different users. The simulation results show that the BER performance of the proposed schemes outperforms existing cooperative transmission schemes and approaches an interference free performance under the same configuration.