Twenty-nine atopic children aged 3-12 years were given elimination diets for 3 weeks, individual groups of foods being then reintroduced over 6 weeks. Most children improved whilst dieting and relapsed on return to normal food intake. In all but 4 cases some food group which caused exacerbation of symptoms was identified, fruits and colourings proving more of a problem than milk and eggs. Taking into account these suspected food allergens, tailored diets were designed for each child. Using these diets the group participated in a double-blind crossover trial of oral sodium cromoglycate (SCG) versus placebo. Twenty-two patients completed the trial. The results indicated that tailored diets were of value in the management of eczema but SCG did not produce a significant additional effect. At follow-up 1 year later most children were adhering to their diet; thirteen were better and only three worse. Children who had initially continued using SCG had stopped it; no accompanying change in their eczema was noticed. A considerable reduction in the use of topical steroids was observed, in marked contrast to previous requirements. Sequential measurements of total serum IgE (PRIST) showed variable changes apparently unrelated to recent SCG therapy. There was little agreement between skin prick tests and specific IgE (RAST) to corresponding foods. Correlation between RAST and food challenge was poor for positive results (r = 0.39) but good for negative results (r = 0.99).