Operation or performance of a fire protection system during a fire depends on several factors such as satisfactory maintenance of the system, location of the fire with reference to the location of the system, rate of growth of the fire or smoke, and environmental conditions. Statistics are available for some of these systems, e.g. sprinklers for estimating the probability of operation of the system in a fire. If the system operates in a fire, it can be effective in reducing the damage likely to be inflicted on life and property. This reduction in damage is a benefit due to the fire protection system at the national economic level which must to be compared with the total costs associated with the system. For a property owner, installation of a fire protection system provides benefits such as tax allowances and savings in fire insurance premiums. This chapter discusses the costs and benefits of individual fire safety measures to the extent that data and research results are available. Combinations of safety measures are discussed in the next chapter.