Complex organisational forms are built through - at least to some extent - interorganisational strategies. To analyse the institutional logic of these forms, the concept of hybrid governance is proposed. This concept is a way to link their structural characteristics with their strategic content. To do so, the suggestion is to consider hybrid governance as an institutional combination of an authority structure and of a coordination architecture in presence of pooled strategic assets. The role of hybrid governance will then be to maximise joint value and minimise organisation costs. Such a perspective helps in the understanding of the very nature of complex organisational forms, of their diversity and of their uniqueness, which can be seen as an optimisation of strategy/structure interplay. From this, it is suggested that the research on hybrid governance is a major theoretical contribution to the chain and network science.