AbstractIntegrated Project Delivery (IPD) is an innovative procurement approach through which the client, designer, and contractor work together under one contract as a team. While an integrated team is expected to be able to create extra value for the project, this practice may bring new risks if not all team members are committed. The slow uptake of IPD may possibly be due to the insufficient understanding of the risks involved, especially those hidden risks associated with inappropriate integration practice. This study identifies critical risks in IPD projects, and investigates if risk criticality can be alleviated by having previous or future partnership between IPD partners. By collecting the views of construction professionals on the level of criticality of general risks and IPD-specific risks, it is found that (1) most highly critical IPD project risks are borne from multidisciplinary teams of poor integration quality, inaccurate target costs, or unreasonable cost estimates; and (2) having future cooperation intent can significantly alleviate the criticality of certain IPD risks, whereas no effect of previous partnership was found on risk criticality. This study contributes to a growing body of knowledge on IPD by providing insight into the effect of new and general risks on IPD project outcomes in particular and clarifying the role of previous/future partnership in risk management. This study suggests active involvement of client and contractors in the design of IPD and signals future cooperation intent to IPD partners during the project process.