The Economic Community of West African States (ECOWAS) was formed in 1975 with the aim of promoting cooperation and development in all fields in the sub-region for the purpose of raising the standard of living of its people through regional integration. This study works from the premises that ECOWAS Treaty has significant implications for West Africa regional development planning and that the contributions of ECOWAS in this direction need empirical investigation. The study sourced socio-economic and infrastructure development indicators on the ECOWAS Member States from institutional and empirical sources; comparing its findings with other selected regional economies. It derived development index for the countries and sought ECOWAS’ intervention level on existing infrastructure and socio-economic situation in the nations. It found out that ECOWAS Treaty has significant implications for West African regional development and that the level of development in each ECOWAS Member State, though low, lacks significant ECOWAS intervention. It then advanced Strategic Rural Development Approach (SRDA) and a Ten Year Ten Sector Intervention Plan (TYTSIP) for West African regional development.