Before revision:  Here, we review the existing results which establish the weak reflection principle for a large class of time-homogeneous diffusions on a real line and, then, proceed to develop this method for all L\'evy processes with one-sided jumps (subject to some admissibility conditions).
After revision:  Here, we review the existing results which establish the weak reflection principle for a large class of time-homogeneous diffusions on a real line and, then, proceed to extend this method to the Levy processes with one-sided jumps (subject to some admissibility conditions).