The existence of strong, sophisticated, perhaps internally coherent and at times even 'learned' antisemitism, where open dislike of Jews is combined with developed negative ideas about Jews, does not exceed 2.4% of British adults, irrespective of the method of measurement used in this analysis. These are people who express multiple antisemitic attitudes readily and confidently. An additional 3% of the population of Great Britain can be termed 'softer' antisemites, expressing fewer, but nonetheless multiple antisemitic attitudes, often couched in less certain terms. This relatively small group of about 5% of the general population can justifiably be described as antisemites: people who hold a wide range of negative attitudes towards Jews. However, because antisemitic ideas circulate in society well beyond this group, there is a much larger number of people who believe a small number of negative ideas about Jews, but who may not be consciously hostile or prejudiced towards them. In total, about 15% of British adults hold two or more of the antisemitic attitudes tested here to some degree at least, and a further 15% of British adults either strongly agree with, or tend to agree with just one antisemitic attitude. Adding these figures together brings the total prevalence of antisemitic attitudes, at different intensities, to 30% of the adult British population.