Several authors have observed that the use of accelerated laboratory testing and Fick's second law for chloride penetration may result to values of the diffusion coefficient one to two orders of magnitude too high compared to the same concrete's real-life behavior. As a result, the validity of using Fick's second law was questioned. In particular, this observation calls for a paradigm shift in the conception of chloride penetration into concrete. Hence in this paper, an alternative approach for further discussion is presented. This alternative concept is illustrated through computer simulation of a two-dimensional random distribution of pores.