The authors provide an approach that enables a power system operator or planner to evaluate his or her alternatives in selecting a certain voltage collapse criterion. Specifically, the selection of a criterion must guarantee that the risk of making a wrong decision is minimal for any operating point and disturbance. This is done by recasting the various voltage collapse criteria in terms of a decision framework. This framework is based on statistical decision theory and provides a method for evaluating the risk of making the wrong decision in terms of the probability of a missed voltage collapse or a false alarm. Some examples are given to illustrate the effectiveness of the proposed approach. >