In recent years, the idea of integration of sustainability into project management has been put forth, which requires a more comprehensive and holistic approach to project management. Integration of sustainability increases the complexity of project management. Therefore, project management organizations require a framework capable of opening up the traditional organization of the project business and providing competitive advantages. This study argues that the open innovation model presents the requisite capability to approach this issue. This research, through a structured review of the literature and an overview of the open innovation and project management knowledge areas, explains how open innovation can provide a fruitful contribution to the integration of sustainable development into project portfolio management and why it should be favoured. The findings show that open innovation can facilitate the environmental, social and economic sustainability of projects, while rendering the project organization more agile.