National information infrastructure (NII), vital to the nation's security and economic stability, comprises both physical and electronic infrastructures. Information and communications technologies (ICT) form the backbone of many aspects of the NII and reliance on ICT has created many new risks. Cyberthreats are becoming more sophisticated with the blending of once distinct types of attack into more damaging forms. This paper examines the technology-related risks associated with the NII and provides examples of existing incidents and areas in which new threats might emerge. To be able to mitigate these risks, it remains crucial to understand infrastructure interdependencies and to establish public-private partnerships to ensure that weaknesses in systems are not able to be exploited.