‘To write a real book about virtual worlds is audacious. To write on virtual worlds, such as the metaverse, before it really exists fully, might seem forgetful of reality. To be ready for the deployment of the metaverse (presented as a network of contracts), actors of many fields need to prepare and adapt to these new challenges. The authors give to the community the full picture of the legal challenges and potential solutions, meeting the expectations of everyone interested. This Research Handbook is not about the future or the virtual, it is about preparing today, in reality, what might well happen in virtual worlds in a couple of years from now. This Research Handbook is the perfect tool to answer many of these challenges, in a thoughtful and effective way.’