The Sandbox: A Lean Validation Framework for the Sustainability of Research Infrastructures

ABSTRACT Research Infrastructures are entering a critical post-NRRP transition phase. As extraordinary public funding cycles come to an end, many infrastructures face increasing pressure to demonstrate long-term sustainability. This challenge is often framed as a financial or organizational issue. This White Paper argues that it is, first and foremost, a managerial decision problem. The document introduces The Sandbox, a lean, decision-oriented framework designed to support the empirical validation of sustainability-related assumptions in Research Infrastructures. Rather than proposing new governance models or sustainability blueprints, The Sandbox focuses on how decisions are made under conditions of uncertainty. Inspired by Lean Startup principles and adapted to the public mission and institutional constraints of Research Infrastructures, The Sandbox treats services, access models, and economic configurations as testable hypotheses. It provides Infrastructure Managers with a controlled managerial environment in which to experiment, measure, learn, and decide before irreversible commitments are made. The Sandbox does not promise sustainability, nor does it replace policy-making or strategic vision. Its contribution lies in reducing decision risk, improving the quality of managerial choices, and enabling evidence-informed governance in complex, resource-constrained environments. This White Paper is intended for Infrastructure Managers, governance bodies, and institutional stakeholders involved in the sustainability and long-term governance of Research Infrastructures, particularly in the post-NRRP context.