Polycentric governance (PG) describes governance systems characterized by multiple, interdependent centers of decision‐making, offering an alternative to centralized governance models. PG is often assumed to be effective at helping policy actors address complex collective action problems, but burgeoning empirical literature on PG shows that it is not a panacea – PG is associated with both positive and negative governance outcomes. In this article, we ask: what do we know about why PG performs well in some cases but not in others? We start with a systematic review, synthesizing findings that provide empirical support for positive and negative features that are theorized to accompany PG. Our review reveals a critical gap in relation to our understanding of PG: the existing empirical literature largely fails to address change and evolution over time in PG systems, undermining our understanding of why PG works – or does not– across different contexts and over time. To fill this gap, we propose a “Context – Operations – Outcomes – Feedbacks” (COOF) framework that draws explicit attention to the interplay between context, operational arrangements, outcomes and identifies feedback pathways and adjustment mechanisms that drive dynamic change and evolution over time.

“Action situations”—events, venues, or physically interdependent instances of decision-making—have become a central unit of analysis in the social–environmental sciences, particularly among scholars interested in bridging the social with the biophysical or ecological side of interdependent decisions. A growing body of empirical studies in social–ecological systems research has recently used case and comparative studies to analyse multiple interdependent action situations, structured into networks. In this article, we take stock of this body of empirical research, synthesize the diverse approaches that scholars have taken to assess “networks of action situations”, and identify fruitful paths forward. We conduct a systematic review of the empirical literature in the field, reviewing and summarizing the key characteristics of the empirical studies, including network features, topologies, methods, and data sources used in each case. We summarize and discuss the conceptualizations, methods, diagnostic procedures, and conclusions used in this body of work in a narrative framework synthesis. The review indicates that an increasingly coherent approach is taking shape, but a systematic, protocol-driven, or formalized approach is only partly emerging. We derive future research needs that could help accumulate knowledge from empirical research.

In the southwestern United States, non-native grass invasions have increased wildfire occurrence in deserts and the likelihood of fire spread to and from other biomes with disparate fire regimes. The elevational transition between desertscrub and montane grasslands, woodlands, and forests generally occurs at ∼1,200 masl and has experienced fast suburbanization and an expanding wildland-urban interface (WUI). In summer 2020, the Bighorn Fire in the Santa Catalina Mountains burned 486 km²and prompted alerts and evacuations along a 40-km stretch of WUI below 1,200 masl on the outskirts of Tucson, Arizona, a metropolitan area of >1M people. To better understand the changing nature of the WUI here and elsewhere in the region, we took a multidimensional and timely approach to assess fire dynamics along the Desertscrub-Semi-desert Grassland ecotone in the Catalina foothills, which is in various stages of non-native grass invasion. The Bighorn Fire was principally a forest fire driven by a long-history of fire suppression, accumulation of fine fuels following a wet winter and spring, and two decades of hotter droughts, culminating in the hottest and second driest summer in the 125-yr Tucson weather record. Saguaro (Carnegia gigantea), a giant columnar cactus, experienced high mortality. Resprouting by several desert shrub species may confer some post-fire resiliency in desertscrub. Buffelgrass and other non-native species played a minor role in carrying the fire due to the patchiness of infestation at the upper edge of the Desertscrub biome. Coupled state-and-transition fire-spread simulation models suggest a marked increase in both burned area and fire frequency if buffelgrass patches continue to expand and coalesce at the Desertscrub/Semi-desert Grassland interface. A survey of area residents six months after the fire showed awareness of buffelgrass was significantly higher among residents that were evacuated or lost recreation access, with higher awareness of fire risk, saguaro loss and declining property values, in that order. Sustained and timely efforts to document and assess fast-evolving fire connectivity due to grass invasions, and social awareness and perceptions, are needed to understand and motivate mitigation of an increasingly fire-prone future in the region.

Over the past several decades, prominent public management and policy scholars have repeatedly identified institutional analysis as a promising tool for empirical research, particularly for the study of ‘new governance’ phenomena where policy is enacted and implemented by actors that span organizations, sectors, jurisdictions, and governance levels. Yet, relatively few empirical studies directly measure and model institutions in management and policy settings. In a systematic review of the literature, we identify challenges and barriers that may prevent management and policy scholars from engaging with institutional analysis, along with examples of studies that illustrate how to overcome these challenges in practice.