Climate change is emerging as one of the primary geopolitical challenges of the early twenty-first century, one that will likely involve military engagements and deployments in both traditional and nontraditional missions. Unlike mass casualty terrorism, climate change does not have a single galvanising event that can encourage collective mitigation efforts by both developed and developing states. International efforts to counter putative climate change causes have, thus far, been only marginally successful. Consequently, some of the more pernicious effects of climate change—extreme weather, heat waves, droughts and floods—will likely continue to manifest in the years and decades ahead. Overall, trends suggest that climate change will continue to emerge as a significant factor that shapes and defines future military missions and deployments.