Since 1866, when first described, colloid milium has been considered uncommon. In 1950, Ferreira-Marques and van Uden1 reviewed the literature and could ascertain only 60 recorded cases. In 1955, Zoon,2 who wrote authoritatively on the subject, referred to colloid milium as "rare." In 1959, Guin and Seale3 presented 7 cases, collected over a period of 6 years, bringing the total number of reported cases to just over 90. Significantly, Quin and Seale state that they "do not believe the condition is as rare as the sparsity of reports would indicate." This article presents a report based on 28 new cases, obtained under the rather particular circumstances of industrial practice in a tropical oil refinery. The first 2 cases were noted the same day, during routine periodic health examination. Histopathological diagnosis initiated further investigation, and over the next 12 months, beginning October, 1957, 28 histologically proven cases were