This paper considers collusion between asymmetric networks in the telecommunications industry. Its primary purpose is to fill the gap between the literature on collusion between asymmetric firms and the literature on collusion in the telecommunications industry. Employing the standard Hotelling framework of horizontal product differentiation with non-linear tariffs and network based price discrimination we allow for differentiation in a second dimension. Modulo locations, the subscribers to each network operator face an asymmetry parameter that directly impacts their demands and can capture asymmetries in demand elasticities, in demand size, or even both. The implications of these asymmetries for the possibility of sustaining collusion are investigated under alternative access pricing regimes.