Community-based observing networks (CBONs) use a set of human observers connected via a network to provide comprehensive data, through observations of a range of environmental variables. Invariably, these observers are Indigenous peoples whose intimacy with the land- and waterscape is high. Certain observers can recall events precisely, describe changes accurately, and place them in an appropriate social context. Each observer is akin to a sensor and, linked together, they form a robust and adaptive sensor array that constitutes the CBON. CBONs are able to monitor environmental changes as a consequence of changing ecological conditions (e.g., weather, sea state, sea ice, flora, and fauna) as well as anthropogenic activities (e.g., ship traffic, human behaviors, and infrastructure). Just like an instrumented array, CBONs can be tested and calibrated. However, unlike fixed instruments, they consist of intelligent actors who are much more capable of parsing information to better detect patterns (i.e., local knowledge for global understanding). CBONs rely on the inclusion of Indigenous science and local and traditional knowledge, and we advocate for their inclusion in observing networks globally. In this paper, we discuss the role of CBONs in monitoring environmental change in general, and their utility in developing a better understanding of coupled social-ecological systems and developing decision support both for local communities as well as regional management entities through adaptive capacity indices and risk assessment such as a community-based early warning system. The paper concludes that CBONs, through the practice of Indigenous science in partnership with academic/government scientists for the purpose of knowledge co-production, have the potential to greatly improve the way we monitor environmental change for the purpose of successful response and adaptation.