This project will assess the impact of e-filing and e-payment in Senegal. The project will produce original causal evidence on the potential of technology for tax administration by closely collaborating with the Senegalese tax authority (DGID). The objective is to answer the following research questions: 1) How did the adoption of e-Filing and e-Payment by large and medium firms in Senegal shape declarative and payment behaviours? 2) Which are the key mechanisms that explain the impacts? To do so the researchers will exploit the recent phased-in adoption of e-services among large and medium firms in Senegal.