Abstract: A waxless or gripping ski base capable of continuous adjustment from a flat-base glide configuration to a stepped-base grip configuration for increased traction, such as may be desired in cross-country skiing. The ski base comprises a plurality of base segments which are pivotally attached to a support member and are subject to adjustment from the flat glide configuration into a variety of nonlinear gripping configurations. This variety of stepped-base gripping configurations is programmed by selection of a unique geometric configuration for displacement contact faces which operate against the base segments to cause their vertical displacement in either a positive or negative direction. The segment adjustment member can be selectively changed to cause the contact faces to displace the segments out of the base line of the ski into a traction configuration which may be either convex or fully extended as in a sawtooth pattern.