Global atmospheric and climatic changes as a result of human activities will significantly alter many elements of the future crop production environment. One of these changes is the rapid increase in tropospheric ozone concentration (\[O3\]). Daily 8-h tropospheric \[O3\] has increased from approximately 10 nL/L prior to the industrial revolution to the current level of approximately 50 nL/L (8-h summer seasonal average), and is estimated to increase further by 20%-25% between 2015 and 2050, and by 40%-60% by 2100. The current ambient \[O3\] is above critical thresholds (40 nL/L) in damaging sensitive crops, and causing substantial yield loss. Future increase in ozone level will worsen this damage. As a major source of food protein worldwide, soybean (Glycine max L. Merr.), the most widely planted dicotyledonous crop and a model of C3 annual plants, is considered as one of the most sensitive crops to ozone exposure. Assessing the impact of the expected increase in ground-level \[O3\] on soybean is therefore of crucial importance for food security of the world in the near future. However, current assessments of the effects on soybean from changes in \[O3\] based on studies conducted in chambers such as growth cabinets, glasshouse or open-top chambers. These facilities modify environmental conditions such as temperature, sunlight, humidity, and hence there is uncertainty over how well they represent the real effects of ozone under conditions of mormal atmosphere coupling in the field. Compared with chamber studies, free-air gas concentration enrichment (FACE) experiment, conducted in fully open-air field condition using regional standard agronomic practices, represents the best simulations for future atmospheric environment. SoyFACE, located at the University of Illinois, USA, is the first interdisciplinary study in the world to investigate the response and adaptation of crops to elevated \[O3\] that will occur over the first half of this century using FACE technology for ozone fumigation. Based on the description of the limitation of chamber studies and operation feature of the SoyFACE facility, this review paper mainly focused on the effects of free-air ozone concentration enrichment on the photosynthesis, canopy structure, dry matter production and distribution, grain yield and its components, as well as insect herbivory of soybean crops, compared the similarities and differences between findings obtained by FACE and enclosure methodologies, and evaluated the interactive effects of ozone by development stages, elevated carbon dioxide concentration and stress treatments (e.g., low nitrogen and extreme climatic events). This fist FACE treatment of a food crop to elevated \[O3\] showed yield losses in soybean under fully open-air field conditions that are at least as large as those predicted from chamber studies. It also showed that the losses may be further exacerbated when elevated \[O3\] is combined with an extreme event. These findings clearly indicated that the impacts of ozone on future food security must be considered as an important factor of global change. The priority areas for future research include the impacts of ozone and its interactions with other elements of global change on major food crops under open-air fumigation conditions, as well as the mechanisms of such impacts and possible regulations in reducing the adverse impacts.