The authors relate the results which have been obtained during the second year of work in a unit set up to support the National Smallpox Erradication Campamg in Brazil. The examination of 105 crusts and 76 vesicular/pustular fluid specimens results in the isolation of 39 and 34 smallpox strains, respectively (Table 1). The time of arrival to the laboratory, influenced the virus isolation rate (Table 2). Close relationship was reached between clinical diagnosis and virus isolation rate (Table 3) when both data were available for comparision. The inoculatlon of eggs betwen 1 to 2 hours after chorio-allantoic mernbrane dropping was shown as adequate in conditions under which tests were carried-out. The laboratory is getting regularly more specimens for diagnosis