Virtual organizations are a complex subject which requires an interdisciplinary approach. In the absence of specific legislation, consolidated doctrine and case law, jurists can resort to three main cornerstones: agreements between members and with third parties, analogical application of laws in force, and informal rules and trade usage. The preliminary step is to define the object of analysis as clearly as possible by building a model definition of virtual organizations for the legal research. On the basis of the model’s features, the most relevant legal issues can be outlined. At present, owing to the very nature of VOs, no definitive solutions are possible. However, some basic indications can be provided to enable potential and effective partners of a VO to understand from the start the possible legal implications of their activities.