Technical Abstract: Giant reed (Arundo donax L.) is a perennial invasive weed that presents a severe threat to agroecosystems and riparian areas in the Texas and Mexican portions of the Rio Grande Basin. The objective of this presentation is to give an overview on the use of aerial photography, airborne multispectral and hyperspectral imagery, and high resolution satellite imagery to detect and map giant reed infestations along the Texas-Mexico portion of the Rio Grande. Aerial color-infrared photographs were taken along the Rio Grande between Brownsville and El Paso, TX, in 2002 and 2008. QuickBird and SPOT 5 satellite imagery was acquired along a section of the river near Del Rio, TX, in 2005. More recently, airborne multispectral and hyperspectral imagery was also acquired along the river near Quemado, TX, in 2009 and 2010. Methods and procedures for image acquisition, processing and classification of different types of imagery as well as accuracy assessment are briefly discussed. Examples are given to illustrate how the different types of imagery have been used to map giant reed. Results from these studies indicate that all the types of imagery can be successfully used to map giant reed. Analysis of the aerial photographs along the river showed that a total of approximately 6000 ha of giant reed infested both sides of the Rio Grande over 900 river kilometers between Lajitas and San Ygnacio. The area estimates are useful for both land owners and government agencies for the estimation of water usage and economic loss and for the management and control of giant reed. Our current research is focused on the use of multispectral, hyperspectral and thermal imagery for the estimation of water use of giant reed and for the assessment of biological control using remote sensing.