Dimensional tolerancing is a language used to communicate product quality specifications. Effective communication using this language relies on there being a common, shared meaning for tolerances. By this measure, the language of tolerances defined in modern standards does not support good communication. Some reasons for this are: the evolution of technology; the lack of research on tolerances prior to the last two decades; and a greater need for rigorous product specifications in a computer environment. I discuss the weaknesses of the language of tolerances and suggest a three-part program of research and standards development to improve it.