There has been debate in the literature as to whether: (1) the risks and benefits of genetically-modified (GM) food and agriculture are considered and determined by individuals separately or whether they are jointly determined by attitudes; (2) consumer acceptance is determined by individuals weighing up their risk and benefit perceptions in a rational, even-handed manner, or if benefit perceptions are more important than risk perceptions, and (3) certain types of risk and benefit are more important than others. Against this background, this paper assesses the categories of risks and benefits and their relative importance in determining willingness to consume. A survey was carried out to collect data on the categories of risks and benefits in the US, UK and France, and the relative importance of selected perceived risk and benefit dimensions was estimated. The findings show: risk and benefit perceptions are negatively correlated, but not perfectly and, given that regressions we performed support the proposition that benefits are more important than risks in determining willingness to consume, a strong case can be made for measuring risks and benefits separately. Almost 2/3 of consumers perceive medium to high potential benefits from GM, though the proportion is slightly lower in the UK and down to 40% in France. Nevertheless, this suggests a much higher level of support for the technology than is normally assumed. From the study, benefits are more important for consumers' willingness to consume than perceived risks, and slightly more interviewees scored above than below the mean on willingness to consume GM food.