Our current environmental situation requires serious attention. We can see the problems that our environment is facing everywhere, including air pollution, ozone depletion, global warming, hazardous waste disposal and water pollution. Today, consumers are aware that their individual consumption behaviour affects the environment and these consumers are more conscious of the seriousness of environmental degradation. Thus, consumers are increasingly engaging in environmentally friendly behaviour and are interested in supporting businesses that are engaging in green strategies. Green purchasing behaviour can help achieve a sustainable environment. Four factors that may influence green purchasing behaviour were examined in this study: perceived seriousness of environmental problems, perceived environmental responsibility, perceived effectiveness of environmental behaviour and concern for self-image in environmental protection. Data were collected from Lebanon, and three factors were found to have positive effects on green purchasing behaviour. The results also indicated that the perceived seriousness of environmental problems was the main contributor to green purchasing behaviour.