The study looked at how foreign investment affects the productivity of manufacturing companies in Nigeria. They used data from the World Bank and different analysis methods to see the impact. The results showed that foreign investment has a positive effect on productivity through certain channels, like making local companies more competitive and improving the quality of materials they use. However, there was a negative impact when foreign investment came from suppliers, possibly due to poor transportation and local companies not being able to keep up. To benefit from foreign customers, local companies need better infrastructure and education.