Delivering reliable, high-quality products at low cost has become the key to survival in today's global economy. The presence of uncertainty in the analysis and design of engineering systems has always been recognized. Traditional deterministic analysis accounts for these uncertainties through the use of empirical safety factors. These safety factors are derived from past experience and do not provide quantifiable measures of the frequency at which failure will occur.Engineering design usually involves a trade-off between maximizing reliability at the component or system level while achieving cost targets. In contrast to the traditional deterministic design, probabilistic analysis provides the required information for optimum design and accomplishes both goals simultaneously. In the automotive industry, quality products are vehicles whose specifications, as manufactured, meet customer requirements. Given the uncertainties in loads, materials, and manufacturing, modern methods of reliability analysis should be used to ensure automotive quality in terms of reliability measures.In large-scale systems, often encountered in the automotive and aerospace industries among others, reliability predictions based on expensive full-scale tests are not economically feasible. Efficient computational methods represent a far better alternative. The first requirement of a computational reliability analysis is to develop a quantitative model of the behavior of interest. Subsequently, the statistical behavior is defined for all random variables involved in the limit-state function that separates the failure and the Zissimos P. Mourelatos