operational level. In particular, given the large number of variables that have been identified as affecting sustainability in some form and their even more numerous potential interactions, a top-down approach driven by theory seems to be necessary to guide the design, execution, and analysis of field studies in ways that make maximal use of scarce empirical research resources.
In summary, the following four chapters provide us with a rich account of the way in which user and user group characteristics interact with resource system characteristics and affect the processes by which institutions are crafted, the types of institutions that emerge, the degree to which they are implemented successfully, and the way in which resulting conflicts are resolved. In combination, they show us that much has been learned over the past 15 years, with some substantive insights and—perhaps more importantly—significant methodological and metatheoretical insights. They also provide us with a road map to yet unresolved questions of commons management design and with an appreciation that complex problems have highly contingent solutions which, in turn, require cross-disciplinary cooperation.