A review of the published work on the flashing of a two-phase flow system, owing to a sudden depressurization of a compressed liquid, is presented. Of concern is the two-phase flow transient occurring during a failure of a pressurized tube or vessel- blowdown. Abrupt depressurization of a confined liquid can bring the liquid to a superheated state. If this occurs, an intense nucleation process is triggered. The level of superheating at which the nucleation process begins is referred to as the "flashing inception" point. The rapidity of the bubble nucleation and growth processes substantial influence the mixture blowdown scenario that sometimes can be in the form of a Boiling Expanding Vapor Explosion (BLEVE). The current review deals with flashing of a single pure substance. First, the models of bubble formation and growth are presented. This is followed by a description on the incorporation of these models into two-phase flow transport models. The two-phase models are used for analysis of the blowdown scenario. This subject is of critical importance for the investigation of the safety of compressed liquid systems.