Significant changes in global climate may be the most consequential issue for human beings. Climate change refers not simply to rising temperatures but to a highly complex phenomenon whose pathway and effects are difficult to project. Wine provides an ideal laboratory for the study of evolving climatic patterns since there is a potential impact on three levels: the plant, fruit and finished beverage. Changes in temperatures in the 20th century have been recorded in numerous countries and regions, and these data and findings are discussed. The existing scientific evidence is examined through the lens of viticulture. Implications for the suitability of cultivars to specific regions are assessed, together with the consequences for prevailing practices and wine taste profiles. The impact to date is seen to be largely benign in marginal areas whereas the long-term threats are judged to be disruptive to varying degrees. Future climate-related changes, if severe, could force a restructuring of viticulture in affected regions.