 The likelihood of successfully co-managing a shared resource, successfully organizing to self-govern, or successfully cooperating in a social dilemma depends on many variables, from the nature of the resource system, to the nature of the social system the actors are a part of, to the political position of external authorities, to the ability to communicate effectively, to the rules-in-place regarding the management of the commons.However, "sub-optimal" or "failed" results in a social dilemma (and perhaps the need for privatization or an external authority) tend to occur "when resource users do "not" know who all is involved, do not have a foundation of trust and reciprocity, cannot communicate, have no established rules, and lack effective monitoring and sanctioning mechanisms.