Shelf life is a critical quality attribute of pharmaceutical product. It is often determined, based on a confidence interval approach recommended by ICH Q1E (2003). Although various alternative methods have been proposed to provide better quality assurance of the drug, it is difficult to evaluate, compare and quantify risks and benefits of each approach due to lack of a common framework. A unified risk-based method in the spirit of QbD will be presented and discussed. The method not only allows for comparing various methods in the same statistical context, but also uses information such as stability of the product, its intended use to guide the selection of proper level of quality assurance.