Figure 1 | Impact, process and response-based approach to understand ecosystem change. Focusing on community processes can enable mechanistic inferences into how humans alter ecosystem dynamics in terrestrial and freshwater systems via effects on community structure and dynamics. Traditional approaches (i) identify various patterns of ecosystem responses and attribute them to specific human impacts, but often do not explicitly consider the community processes which shape these responses, in particular across ecosystems. By considering these processes we can better fill the twin knowledge gaps of (ii) how humans change the relative importance of processes operating in communities, and (ii) how these processes then create the observed ecosystem responses.