Public wariness of genetically modified (GM) foods has led many nations to develop labelling policies for foods derived from modern agricultural biotechnology. In most cases mandatory labelling has been specified. In contrast, voluntary labelling is the chosen policy approach for the United States and Canada. Detailed regulations to enable a voluntary labelling policy to become effective in Canada have been time-consuming to develop. An even longer period of time has applied in the case of unsuccessful efforts to develop consensus standards for GM food labelling at the international level, through the processes of Codex Alimentarius.