The next step is to choose the most appropriate method or tool for open innovation, depending on the nature and complexity of the problem, the availability and diversity of the stakeholders, and the resources and time constraints. There are many methods and tools for open innovation in the public sector, such as crowdsourcing, hackathons, innovation labs, living labs, citizen science, open data, and public-private partnerships. Each method has its own advantages and disadvantages, and requires different levels of participation, collaboration, and feedback. A good practice is to combine different methods and tools, to create a holistic and flexible open innovation process.