This chapter focuses on the application of the World Health Organization Framework Convention on Tobacco Control (FCTC) in West Africa, and how the use of action research to generate evidence and the creation of consensus between the different stakeholders involved in tobacco control can change policy. The evidence produced and the actions undertaken have contributed to the adoption of a new law on tobacco control in Senegal and a new directive on the taxation of tobacco products in the Economic Community of West African States area, which is now better able to comply with the provisions of the FCTC. A particularity of the taxation of tobacco in West Africa was the lack of country-level studies and data. Tax administrations saw the taxation of tobacco products as an instrument for collecting tax revenue, while civil society actors and ministries of health focused on the health dangers.