The motivation for this paper was to create a theoretical framework that would capture model tools for analyzing competition between interconnected networks providing services of new network industries. The formal framework is based on game and negotiation model approaches. The models are devoted to analysis of specific issues. Critical elements of competition are terms and conditions of the access arrangements between networks. Access fees are determined either by a regulator or by competition. The models analyze when network competition is sustainable without regulation, and how regulation can promote sustainable network competition when it is not. The sustainability of competition between networks is influenced by initial market share allocations, propensity of subscribers to switch networks, fixed costs of operations, and a market’s price. The impact of competition between networks on negotiation and integration within a network is analyzed also.