The food systems that provide the caloric requirements for most of the world’s population are plant-based, including, rice, wheat and maize. The health and productivity of plant systems is a prerequisite of food security and human health. There are many general threats to plant systems that put plant biosecurity at risk, including global trade of plants and plant products, climate change, population growth and landscape exploitation. Bioterrorism is one more threat to consider when developing a strategy for plant biosecurity. Plant systems are vulnerable to biocrime and bioterrorism. Various lists of threat agents and different approaches to risk assessment have been developed to guide research and policy decisions. Yet an integrated strategy for global plant biosecurity is lacking.