This thesis investigates how collaboration for defence innovation may be organised and function in an international context, given traditional constraints on exchange and non-inclusive posture toward outside of national state actors. Drawing on innovation and military innovation studies, the study explores how selected key players interpret the contemporary phenomena of the Portuguese operational experimentation exercise REPMUS. The exercise is designed to advance capability in the field of maritime unmanned systems (MUS), an innovative area with disruptive potential, using a triple-helix approach. The findings reveal a collaborative model for mediating between top-down and bottom-up initiatives to incentivise participation from a broad spectrum of actors. Meanwhile the model places an emphasis on national systems of innovation (NSI) and state sponsorship, contemporary challenges and the need for rearming Europe is expected to gradually transform the ways to interact toward international collaboration, possibly altering the institutional logics of industry, academia and state spheres.