The objective of this paper is to discuss the application of GIS technology for a perennial weed biocontrol program. The GIS based survey and mapping of perennial species has provided the baseline data for setting priorities for target weeds. Application of GIS for biocontrol program management will be discussed. Topics will include use of GIS to: identify problem areas; choose release sites; evaluate and monitor establishment of biocontrol agents and their impact on weed populations. Other GIS applications to be discussed include: evaluation of risk potential of weeds based on landscape characteristics; and justification of the biocontrol agent screening process.