Iron deficiency anemia is the most prevalent nutritional deficiency in the world and food fortification is a cost-effective approach to combat it. This paper reviews the food fortification process with micronutrients, with special emphasis on iron and the most critical steps and common difficulties found when implementing a program. The first step is to measure the magnitude of the problem and the groups affected by iron deficiency and anemia, to determine if there is a need for fortification. Then the adequate iron compound and vehicle should be selected, to obtain a bioavailable form of iron in a frequently consumed food item without changing the taste, appearance or cooking characteristics of the final food item or complete meals containing it, to assure the acceptance by consumers. Before implementation, bioavailability studies are in order for the fortified food item and for complete meals especially typical or traditional meals, followed by field studies and pilot tests. Once implemented, the program should be monitored and evaluated continuously, and the impact on health assessed periodically to give the program the flexibility for continuation made changes or finalization when necessary. Other key elements for successful implementation of food fortification programs include the presence of a viable food industry; available channels for food marketing and distribution; a health care system to identify and monitor micronutrient malnutrition in the population; institutions for education, treatment and evaluation of the impact of the program; and continuous and effective input into the planning, implementation, monitoring and evaluation of the intervention to ensure sustainability of the intervention.