Economic success in operating PV systems depends essentially on the likelihood of their long-term operation and their delivery of the expected energy yield. These requirements, for which a lifetime of 20–25 years is often assumed, are demanding and cannot be met without preparation. Preconditions are the acceptable quality and long-term stability of the products employed (particularly the PV modules, but also all other components and materials) and the absence of damage to these items during transport and handling. Moreover, PV systems must be professionally planned and properly implemented. This includes considering energy yield assessments not only in the initial estimation of the energy yield, but also in the subsequent planning for concrete implementation. In addition, professional operational management and appropriate maintenance measures will ensure operation with maximum availability. Yield insurance policies can safeguard profitability and render the risks calculable; various models exist for this purpose and these must be carefully tested. It is important that the insurances services also cover the possible insolvency of the responsible system and component suppliers.