Abstract: The present invention is concerned with self-righting drinking cups and provides for a two part cup, the first part of which is a generally hollow cylindrical liquid container, and the second part of which is a base for the liquid container. The base member has a convex surface progressively decreasing from its junction with the drinking cup proper to the lowermost portion of the base.Certain dimensional ratios are critical to the self-righting performance of the cup. The diameter of the lowermost portion of the base must be about 0.39 to 0.75, preferably 0.39 to 0.65, and most preferably 0.40 to 0.60 of the greatest diameter of the drinking cup itself.Further, the critical ratio of cup height to maximum cup diameter must be about 0.80 to 1.1, preferably about 1.02 (about 1).Further, the critical ratio of cup height to the diameter of the lowermost portion of the base must be about 1.3 to 2.5, preferably 1.3 to 2.2, and more preferably about 2.13.