Herbicide-tolerant varieties account for over 90% of the canola grown in western Canada and most of this is tolerant to glyphosate. Field experiments were conducted at three locations in Alberta to compare the glyphosate system with more traditional herbicide regimes. Glyphosate applied prior to seeding in spring resulted in better weed control, lower dockage and higher canola yields and net revenue than 2,4-D applied in the fall. Glyphosate applied once or twice in-crop provided similar weed control, dockage and canola yield as a combination of pre-emergence ethalfluralin (fall applied ) followed by an in-crop mixture of sethoxydim, ethametsulfuron and clopyralid; and superior weed control and canola yield and lower dockage than ethalfluralin alone or an in-crop mixture of sethoxydim and ethametsulfuron. The in-crop glyphosate applications also resulted in higher net revenues than the other treatments. Overall, however, there was little or no advantage to applying glyphosate twice compared to once in-crop. The amount of active ingredient entering the environment varied with the herbicide regime but was lower with the glyphosate system than with most of the traditional regimes when glyphosate was applied only once in-crop.