Project portfolio management is a systemic approach to managing multiple projects, programs, and operational activities collectively to achieve strategic objectives. It involves centralizing the identification, evaluation, selection, prioritization, and oversight of these initiatives to optimize resource allocation and maximize organizational value. As an academic concept and research field, it investigates the principles, processes, and governance mechanisms by which organizations strategically align their investment in change initiatives, balance competing demands for resources, and monitor portfolio performance against strategic goals. Key characteristics include structured selection and prioritization frameworks, cross-initiative resource management, portfolio-level risk assessment, and adaptive governance. Its significance lies in its critical role in enabling organizations to effectively execute strategy, improve decision-making regarding investments in change, and enhance overall performance by ensuring the right initiatives are undertaken and managed effectively within resource constraints.