A methodology is described for allocating reliability to various nuclear reactor systems, subsystems, components, operations, and structures consistent with a set of global safety criteria that are not rigid. The problem is formulated as a multiattribute decision analysis paradigm; the multiobjective optimization, which is performed on a probabilistic risk assessment model and reliability cost functions, serves as the guiding principle for reliability and risk allocation. The concept of “noninferiority” is used in the multiobjective optimization problem. Finding the noninferior solution set is the main theme of the current approach. The assessment of the decision-maker’s preferences could then be performed more easily on the noninferior solution set.