This paper addresses the question of the coherence in the infrastructures. More precisely, it examines the articulation between technical and institutional coherence. It assumes that a certain degree of such coherence is necessary for infrastructures (network industries) not only to properly function, but moreover to be both economically and socially performing. The paper takes the current unbundling of the electricity and the railways sectors as cases so as to analyze whether and how the dynamics of deregulation (liberalization) leads to such incoherence. It is therefore grounded in organizational behaviour and institutional analysis and focuses on the strategies of the actors in a liberalized environment. The paper is therefore primarily conceptual in nature, as it seeks to frame the dynamics of the liberalizing network industries in terms of a co-evolution between technology and institutions.