The objective of this report is to review the requirements for disturbance information, the manifestation of damage patterns that may be encountered, and to provide an overview of remote sensing sensors and change detection methods that have been, or could be applied to mapping of insect defoliation and aspen dieback. It was developed with financial support from the Canadian Space Agency (CSA) by the Canadian Forest Service (CFS) and the Canada Centre for Remote Sensing (CCRS) as part of a Government-Related Initiatives Program (GRIP) project entitled “Gauging the Health of Canada’s Forests: Accounting for Insect Defoliation and Dieback in the Indicators of Sustainability for Canadians”. The report was first submitted as a deliverable to the CSA in 2007 and reviews the utility of both optical and radar remote sensing sensors and change detection approaches. For this release of the report as a Geomatics Canada Open File, the text was revised in part to relay major developments regarding the availability of satellite sensors and change detection methods in particular. A comprehensive review of literature published after 2007 was beyond the scope of the revision. A recent review paper by Hall et al. (2016) draws from this report but is limited to a discussion of the utility of optical sensor systems and change detection methods.