Innovation portfolio management (IPM) addresses the resource allocation across a firm’s portfolio of new product development projects consistent with corporate strategy. The paper provides a comprehensive review of IPM research and offers new conceptual arguments by systematizing prior findings in the following four categories: optimization perspective, strategic perspective, decision-making perspective and organizational perspective. These different approaches to IPM have been largely disconnected so far, but they can complement one another to provide new theoretical insights into a critical topic in innovation research. The different approaches are therefore integrated into an overarching perspective and a detailed research agenda is proposed.