Piercing the earlobes has increased in popularity among males in recent years. This habit would be expected to increase the incidence of nickel and cobalt sensitization. Patch testing with nickel sulfate and cobalt chloride was performed in 520 young Swedish men doing compulsory military service. The overall frequency of nickel/cobalt positive tests was 4.2%. The prevalence of nickel/cobalt positive tests was significantly higher (p < 0.05) in 152 men with pierced earlobes (7.9%) than in those 368 with unpierced earlobes (2.7%). A history of hand eczema (7/152 = 4.6%) or other types of eczema (22/152 = 14.5%) in individuals with pierced earlobes was no more common than in those with unpierced earlobes: 24/368 = 6.5% and 51/386 = 13.9%, respectively (n.s.). Hand eczema was no more common in sensitized (1/22 = 4.5%) than in nonsensitized individuals (32/498 = 6.4%) (n.s.).