The relationship between state sovereignty and investor right is well discussed in academic circles. However, when these concepts are nested with major issues such as investment screening and narrowed in the natural resource sector, the outcome points to the fact that academic conversatiosn on the issues are still embryonic. Indeed, investment treaty arbitration has increasingly come under attack because it has the propensity to elevate investors ahead of host states and afford foreign investors broad investment rights they can invoke and pursue upon minimum regulatory changes. The threat of substantial arbitral award can result in host states not enacting policies, regulations, laws or reaching decisions despite them being needed. This thesis analyses investor-state dispute settlement in Africa with a narrow focus on the natural resource sector and questions the legitimacy of these mechanisms and whether they can strike an appropriate balance between investment screening and state sovereignty and investment protection. secondly the thesis assesses whether investment screening can be deployed the potential conflict between investment screening and and state sovereignty and to ehat extent this conflict resulst in the phenomenon of "regulatory chill". the study concludes on the extent to which investor state arbitration can resiolve the seemingly conflict and offers recommendations.