A cost effectiveness study was conducted with the main objective to assess the operational costs of a vaccination campaign against yellow fever organised and implemented in Abidjan from September 21st to October 2nd, 2001. The study was carried out from the perspective of the health authorities. Data was collected retrospectively on all information related to resources needed and required activities. The justification of the monetary value of resources was provided with written proof and receipts as well as other supporting documents. The coverage achieved was 91.33% with 2 584 360 doses of vaccine having been administered. Spending on vaccines and vaccine supplies amounted to 1 123 177 128 FCFA; the average cost per dose was 539.40 FCFA. Human resource costs amounted to 2590 people who were mobilized for a total cost of 125 678 400 FCFA. The total operational cost of the vaccination campaign was 1 394 010 829 FCFA. Vaccines and supplies were the largest item of expenditure, or 80.57% of the total spent. The results of this study could serve as a tool for decision-making related to funding a vaccination campaign. Taking account of these results could contribute to the development of strategies to effectively reduce the operational cost of a vaccination campaign.