The increasing incidence of peanut allergy prompted this group to look at the predisposing factors to the condition. A subgroup of 49 children with a clear history of peanut allergy was identified from the Avon longitudinal study (a cohort of 13 971 preschool children). Information was obtained from questionnaires, medical records, and cord blood. Peanut allergy was confirmed by double blind, placebo controlled food challenge in 23 of the 36 children tested. Allergic responses to food challenge included bronchospasm, stridor, and angioedema. Significant associations with peanut allergy were found with soy milk/formula consumption (odds ratio 2.6), family history, and history of atopy. Interestingly, rashes over joints (odds ratio 2.6) and the use of skin preparations containing peanut oils to these rashes (odds ratio 6.8) were associated with peanut allergy. The group hypothesised that allergic sensitisation occurs to peanut antigens through inflamed skin as they are present in emollients used for the treatment of diaper rashes, eczema, dry skin, and inflammatory cutaneous conditions. More trials are needed, however, and, if this is the case, avoidance of exposure to emollients containing peanut oils may prove to be a cost effective therapeutic intervention.