Effective Stakeholder Management (ESM) has been identified as one of the key requirements for successful project delivery by several scholars. This study, aimed at improving the chances of achieving successful Multifarious Infrastructure Projects' (MIPs) delivery in Nigeria, was conducted through literature review, questionnaire survey and Relative Importance Index (RII) method of data analysis. The study identified 39 barriers to ESM in the delivery of MIPs in Nigeria, evaluated their respective impacts on projects' delivery and ranked the barriers in ascending order of their respective impact levels. Failure to understand stakeholders' needs and expectations, uncooperative attitude of stakeholders, failure to identify key stakeholders, failure to identify potential conflict areas, project manager's poor knowledge of stakeholder management (SM), late identification of stakeholders, issuance of incorrect information to stakeholders, lack of stakeholder engagement/involvement, conflicts between stakeholders, misunderstanding of roles by stakeholders, lack of fairness and equity for all stakeholders and lack of continuity in SM process were ranked as the ten top barriers ,in descending order, with highest levels of impact against ESM in MIPs delivery. The study also provided MIPs managers with an insight on the barriers to address/focus on in order to achieve ESM in the delivery of their projects. The study concluded that there was need to pay special attention to the above barriers due to their high impact level on ESM and improve current approaches to stakeholder management in MIPs delivery in order to improve the success rate of the projects. The study recommends development and effective implementation of an appropriate strategy for handling stakeholder management in the delivery of MIPs and other projects.