Geophysical survey applications to cultural resource management (CRM) archaeology have been underused and underappreciated in most planning jurisdictions in Ontario. As a result, there has been little desire to incorporate geophysical applications into professional standards, given a general lack of confidence or understanding of proper methodologies by the approval and regulatory authorities (Lockhart and Green 2006). ASI has tested appropriate geophysical survey applications during several archaeological site investigations in Ontario. This poster presentation will examine three of these sites: the Damiani site (AlGv-231), Blacker’s Brickworks (AgHb-415) and the Fort York National Historic site-Government House Area (AjGu-28), which resulted in positive identification of sub-surface archaeological deposits, guiding the excavation and interpretation of the sites.These surveys represent positive and replicable initiatives of geophysical survey application to archaeological investigations in a CRM context in the province. The following will describe each site, the survey, the results and the interpretation of the results in an archaeological excavation context.