Costs and costing information is an important and useful input to the routine planning, budgeting, management, and implementation or rollout of an effective immunization program. This information is also needed when conducting economic evaluation studies to determine what, when and how to introduce new vaccines or which implementation approach/strategy would achieve better and effective coverage. The costs are not generalizable from one country to another as vaccine schedules, target populations, strategies etc. vary by country. For this reason, costs are country-specific and should be obtained and estimated locally. This module provides information on the cost profiles of routine immunization programs and supplementary immunization activities (SIA) using different country examples. We will learn how to cost existing programs, specific interventions, new vaccine introduction, and possible data sources to conduct such analysis and how to report and use the results for policy decisions.