By means of a prospective study design and multivariate regression analyses we have studied the relative importance of atopy, metal dermatitis and earlier hand eczema as risk factors for the development of hand eczema in women during 20 months of "wet" hospital work. The population consisted of 1857 women. The prevalence of hand eczema during the observation period was 41%. The risk of developing hand eczema was calculated as predicted relative odds ratios. The interrelationship of the risk factors was analysed. A summarized description of this analysis shows that a history of earlier hand eczema increased the odds by 12.9 times, a history of metal dermatitis by 1.8 times and atopic dermatitis and atopic mucosal symptoms by 1.3 times. Thus a history of earlier hand eczema seems of crucial importance for the occurrence of hand eczema in women in ´wet´ hospital work. Our hypothesis is that a history of earlier hand eczema may be considered a major indicator of a skin vulnerability factor predisposing the individual to hand eczema. If the hypothesis is true, this factor may be present approximately in one half of the subjects with atopic dermatitis, in one fourth of the subjects with atopic mucosal symptoms and in one fifth of the non-atopics.