This project aims to improve the longterm profitability of primary producers by developing novel biocontrol solutions that reduce the recurrent costs of weed control. It focuses on African boxthorn and Cabomba, which are Weeds of National Significance and fleabane and Sowthistle which are widespread agricultural weeds that have developed herbicide resistance in recent years and are now extremely difficult to manage with currently available methods. The project expects to: (i) Characterise invasion pathways of the target weeds and identify new agents through the application of advanced molecular techniques; (ii) Make geographic projections of potential distribution and impacts of new agents to control the target weeds; (iii) Develop new biocontrol agents for safe for release into Australia; (iv) Deploy approved biocontrol agents and explore suitable ways to integrate novel biocontrol solutions with other on-farm and off-farm weed management techniques.