Abstract: An in-line roller skate assembly having at least three running rollers that are substantially equal in diameter and disposed one behind the other in a running direction of the skate assembly. Each running roller has a convex shaped rolling surface with a pair of laterally spaced curved shoulder portions having a common radius of curvature as defined in a plane intersecting a rotational axis of the respective roller. The radius of curvature of the curved shoulder portions of the front and rear rollers are greater than a radius of curvature of each curved shoulder portion of the intermediate roller or rollers.