We address the question of finding sensors’ coordinates, or at least an approximation of them, when the sensors’ abilities are very weak. In a d dimensional space, we define an extremely relaxed notion of coordinates along dimension i. The ranki of a sensor s is the number of sensors with ith-coordinate less than the i-coordinate of s. In this paper we provide a theoretical foundation for sensor ranking, when one assumes that a few anchor sensors know their locations and that the others determine their rank only by exchanging information. We show that the rank problem can be solved in linear time in R and that it is NP-Hard in R2 . We also study the usual localization problem and show that in general one cannot solve it; unless one knows a priori information on the sensors distribution.