A broad range of participatory methods can be employed to understand the vulnerability of social–ecological systems threatened by various drivers of change including climate change and land-use change. Understanding this vulnerability is critical for managing natural resources, particularly water resources that flow across jurisdictional boundaries, and support conflicting uses. This paper demonstrates Q-methodology, a promising participatory method infrequently applied in the vulnerability context, with a case study investigation of the vulnerability of stakeholders reliant on water-based ecosystem services derived from the Shoshone National Forest in Wyoming, USA. The approach identified four distinct viewpoints regarding vulnerability, including an environmental perspective, agricultural perspective, Native American perspective, and recreation perspective. The distinct viewpoints highlighted disparate levels of importance related to 34 water benefits, such as commercial irrigation, oil and natural gas extraction, river-based fishing, and cultural and spiritual use. A diverse range of drivers of change threatening important water benefits were also identified, including pollution, too much management intervention, and development of recreation opportunities. The potential benefits of Q-methodology for vulnerability assessment include a rank-ordering exercise that elicits preferences for tradeoffs, and statistical derivation of a small number of perspectives about the topic.