Abstract: In China, since the theoretical research on discretional undertaking has not yet put into full swing, there are a large number of problems at the level of implementation which need to be resolved by researchers in this field. However, because of the system of discretional undertaking itself has not developed into its mature phase, then it is not the best choice to do systematic study in the application of the theory. Judging from the situation, this paper does not deal with the general picture from all levels, instead, it illustrates the theory of discretional undertaking through the perspective of several difficult problems in various cases.