Structural wedges are an integral feature of the three suborogenic belts that comprise the southern Canadian Cordillera. Overall, the southern Canadian Cordillera is a bivergent orogen flanked on the east by the Rocky Mountain fold-and-thrust belt and on the west by the Cascadia subduction zone. Nested within it are two regional structural fans: the Selkirk fan in the western Rocky Mountain Belt and the Coast Belt fan. Geometric information obtained from seismic reflection data in the core zones of these structural fans are shown to be consistent with models that suggest tectonic delamination of material from the downgoing plate by a wedge-shaped undeformed upper plate. In contrast, tectonic wedges at the flanks of the orogenic prism consist of deformed material that delaminated the autochthon, or upper plate. Tectonic wedges occur at various crustal levels and tectonic settings. Within the upper crust, east-directed thrust wedges occur at the eastern flank of the Rocky Mountain and Coast belts. Within the middle and lower crust, beneath the western Rocky Mountain and Coast belts, crustal slivers delaminated from the eastward subducting plate were placed onto the western margin of paleo-North America. At the crust-mantle boundary in the interior of the Cascadia subduction zone, delaminated material from the eastward subducting oceanic plate apparently was added to the upper North American plate. These crustal reflection data, along with similar observations from other collisional settings, are interpreted to indicate that tectonic wedging and delamination is a fundamental feature of crustal deformation. Tectonic wedging explains the origin of two-sided orogenic belts with coeval deformation at flanking extremities. Tectonic wedging in the core zone of orogens is not readily recognized from the surface and implies a different structural stacking order than that predicted by the in-sequence addition of thrust sheets to the hanging wall or footwall of the orogenic prism.