Research infrastructures are long-term enterprises. They are increasingly diverse in nature, may operate under very different models of governance and financing, and within diverse and evolving financial and political contexts. They represent strategic investments which are indispensable for enabling and developing research in all scientific domains and also often have broader socio-economic impacts. This report identifies the challenges faced by research infrastructure funders, managers and operators all along the various phases of the research infrastructures life-cycle, presents practical solutions that have been found to be applicable in certain cases, and proposes a series of policy recommendations which could be implemented to increase their effectiveness and sustainability.