The study of the form, significance and development through time of erosional slopes has long held a nodal position in geomorphology, a study upon which have been focused most of the subject's methodological disputes. Thus, for example, the early nineteenth century 'diluviaP versus uniformitarian controversy, the midnineteenth century marine versus subaerial wrangle, the Davis versus Penck debate and the most recent conflicting landscape interpretations based either on cyclic versus non-cyclic notions, or on 'contemporary' versus past processes seem to have been contracted and intensified when viewed in the context of erosional slope studies. The importance of erosional slopes lies not only in their widespread character, but in their geometrical importance in constraining regional morphometry in such a manner as to permit characteristic 'regional landscapes' to emerge. Strahler (1950, p. 685) has pointed out that, together with drainage density, relief and the upper slope curvature, maximum valley-side slope angles represent a most important morphometric parameter whereby whole erosional landscapes may be characterized. The third, and most important, reason for the nodal position assumed by the study of valley-side slopes (i.e. their broad significance in terms ofthe force/resistance ratio) will form the point of return at the end of this paper. Slope studies have always been among the most perplexing which have faced the geomorphologist for several reasons. To begin with, the detailed forms of erosional slopes have been difficult to obtain without precise field surveying. This is both because the human eye is extremely deficient in estimating slope angles and forms in the vertical plane (Vernon, 1937, p. 139), so that, for example, dominantly straight slopes usually appear concave to the visual observer, and because valley-side profiles (unlike longitudinal stream profiles) cannot be at all satisfactorily obtained from even the most accurate contour maps in common use. The second difficulty lies in the essentially varied and complex character of slope forms and in the multivariate nature of slope processes. Individual slope profiles are mathematically complex, so that in the past attention has been variously concen? trated on the upper convexity (Lawson, 1932), the lower concavity (Lake, 1928), or the middle straight segment (Strahler, 1950). To increase their difficulties, geomor? phologists have been constantly concerned as to whether the actual surface or the bed-rock surface constitutes the 'reaP slope profile. Similarly, this complexity of individual slope form is believed to mirror a complexity in the assumed controlling structures, processes or erosional histories. Nor does the wide range of characteristic slope angles between different geomorphological regions (Strahler, 1950, p. 680) entirely mask the local variations in slope angle which probably have so much to teach us regarding the circumstances responsible for them (Strahler, 1950, p. 812-13; Melton, 1960; Carter and Chorley, 1961). In all these respects multivariate techniques (Melton, 1957; and Krumbein, 1959) have much to offer the researcher, but they must be used rationally so that co-variation due to some undetected common cause, or occurring by chance, can be distinguished from that possibly due to cause and effect. The third impediment facing slope studies is the doctrinaire attitude of most researchers, which is both a cause and an effect of the methodological importance which has been assumed by these studies. Little need be said here regarding the sources of partiality resulting from strongly held cyclic, poly-cyclic, posthumous climatic, climatic morphometric or, for that matter, dynamic/equilibrium notions, to which some reference will be made later. A further impeding source of partiality lies in the assumed minor importance of studies of present processes. This attitude emanates largely from a preconceived notion of the importance of correlations between present forms and the long-past events which are wholly believed to account for them; from the recognition of the complexity of present processes; from the current lack of knowledge relating to