In Chapter 5 it is demonstrated how additional benefits and/or failures from incremental risks may be used to achieve sustainability, through the management of multiple risks. These are the 4Es risks: (1) Engineering (epistemic), (2) Environmental, (3) Economic, and (4) Equity (social) risks. After defining the risk as a function of different performance indices of a system, the “optimisation” approach through mathematical programming is illustrated for minimising one‐dimensional risks (e.g. technical/economic/environmental/social). The basic decision theory under certainty, under uncertainty, under conflict and under risk is explained together with the utility concept. When multiple risks are simultaneously taken into account (e.g. technical and economic and environmental and social), then the Multiple Objective Decision Analysis (MCDA) is suggested for effective risk management. Examples of application and questions and problems with answers in Appendix C enhance the reader's understanding.