Community contextual factors including community perceptions and institutional capacity are among the key determinants in community-based water resource management. The Institutional Analysis and Development (IAD) framework proposed by Ostrom is commonly employed to examine the outcome of common-pool resource management including water resources. However, community perceptions typically examined in behavioral economics and comparative community analysis literature are rarely incorporated in institutional analysis studies. This study draws on the IAD framework to investigate smallholder farmer communities' responses to water scarcity in arid northwestern China. Adopting alternating multiple regression and multivariate regression models, this study conducts an empirical analysis using farmer survey data. The results show that the perceptions of water scarcity promote community actions in coping with water shortage. The perception of production risks encourages overall community responses, as well as farmingand irrigation-related responses. Communities with a stronger institutional enforcement are more responsive in taking farming-, irrigation-, and infrastructure-related actions, as well as having better overall responses. The analysis also shows that community interactional capacities and socio-economic factors may influence community actions to mitigate and adapt to adverse effects of local water scarcity. Our findings provide insights for understanding social and institutional aspects of rural farming communities toward sustainable response decisions to overcome water scarcity challenges.Sustainability 2019, 11, 483 2 of 21 variations of community-based approaches emerged and were largely considered for adoption in many developing nations [3,6,7].To effectively and efficiently manage water resources, rural communities are the focal point and the community approach demonstrated a successful strategy with a wide range of development pathways [7]. The pathways can create opportunities for rural communities to tailor and implement their own plans for water management and development processes. Through pursuing socio-economic objectives of rural communities, the approach facilitates linkages between water resource conservation and community livelihood enhancement [8,9]. For instance, evidence was found in a variety of settings that community engagement improves sustainability of water supply systems [6,8,[10][11][12][13], water quality improvement [14], conflict management [15], and other social outcomes [16]. Kativhu et al. [10] observed that the sustainability of water supply facilities could be improved through building stronger capacities in technical, social, and institutional aspects. Schnegg and Bollig [17] found that a stronger community capacity (with a strong kinship and reciprocity) facilitated rural water users to more effectively manage water resources during a drought compared with formal water agreements. Thus, the community-based approach can enhance local people's ability to reshape the biophysical...