Modes of rock slope movement in the sedimentary sequences in the Canadian Rockies are determined by the relationship between the orientation of the slope and penetrative discontinuities. Major rock slides occur on overdip, cataclinal slopes and move along bedding surfaces whose dips slightly exceed the basic angle of friction. Overdip slopes evolve to dip slopes as a result of sliding. Buckling occurs on dip slopes and limits relief development. Two toppling modes develop on underdip, cataclinal slopes, block flexure topples and block topples. Sliding surfaces develop in block topples, along which rock masses are displaced. Large topple-slides occur on steepened escarpments and reduce slope gradients. Rock beds topple from bedding and slide along combinations of bedding and kathetal joints or along sheeting joints.