Idowu Sulaiman ABDULSALAM2024-05-302024-05-302022-12Kate TurabianM.Schttps://repository.lcu.edu.ng/handle/123456789/418The study examines the relationship among economic openness, agriculture, industry, finance and service sectors in Nigeria covering the period 1985 to 2019. The data were analyzed using descriptive statistics, Toda and Yamamoto causality test, Autoregressive Distributed Lag (ARDL) co-integration test, impulse response functions and error correction mechanism. The study found that the data for some variables were fixed at level while others were integrated at first differentiation. Findings from the study reveals that causal relationship exist only between service sector and trade openness. Furthermore, the study describes a long-term relationship between economic openness and sectoral output growth in Nigeria. However, there were mixed results in the short run, from the impulse response pictures, it shown that most of the variables fluctuated along the periods. The study therefore recommended that government should diversify Nigeria economy away from oil, provision of sophisticated farm tools and infrastructural facilities, formulation and implementation of fiscal and monetary policies among others. Keywords: Economic Openness, Economic Growth, Sectoral Output, NigeriaenEconomic OpennessEconomic GrowthSectoral OutputNigeriaservice sectorsThesis