To ensure the vital interests of the megalopolis in strategic management, it is necessary to proceed from the principles of the necessary reliability of protecting the vital interests of the individual and society, as well as the information security of the megalopolis, a balanced composition of forces and means of protection, the adequacy of countering information threats.

As indicators of the reliability of protecting the vital interests of the individual, society and information security of a megalopolis, we can use the value of the level of integral prevented damage in the socio-economic sphere.

The specific weight of the integral prevented damage in the political, economic, environmental, information and other areas of the socio-economic sphere of the metropolis will be different.

It is advisable to assess the reliability of protecting the vital interests of the individual, society and information security of the megalopolis by the criterion-the probability of protection. Depending on the capabilities of representative and executive authorities in various areas of the life of the metropolis, factors and conditions of information threats, as practice shows, it is advisable to introduce levels of the criterion of reliability of protective measures, for example, low (probability – 0.3), medium (probability – 0.5–0.6), high (probability – 0.8–0.9).

One of the leading principles for determining potential and prevented damage is the principle of reliability, which consists in establishing by the method of expert assessments the significance of damage to information security in the socio-economic sphere from the impact of information threats, based on the balance of vital interests of the individual, society and the metropolis.

The main criterion indicator in the problem under consideration is the amount of potential (prevented) damage to the information security of a megalopolis in the socio-economic sphere due to the implementation of the impact against information threats.

The assessment of direct and indirect damage, as well as the positive and negative consequences of measures that ensure prevented damage, is extremely difficult, mainly because of their manifestation in the most diverse, often difficult to compare, spheres of activity of the metropolis.

To determine the integral potential and prevented damage from the impact of a set of threats in the socio-economic sphere, it is necessary to bring a set of partial estimates into a comparable form.

At the same time, taking into account the specific difficulties associated with the inability in most cases to express the damage caused to the security of a megalopolis in a number of areas in the form of a direct cost estimate, it seems appropriate to use the so-called «relative importance» scale. The methodological basis for this is the method of expert assessments, which is rationally combined with the use of methods of objective quantitative assessment of damage in the form of value. At the same time, the assessment of possible damage is measured by appropriate qualitative, and in some cases quantitative indicators (for example, in the form of material damage), obtained by calculation or expert means.

The development of a methodology for determining the size of potential damage to the information security of a megalopolis can be used to assess the prevented damage in the socio-economic sphere of a megalopolis. At the same time, the reduction of the influence of subjectivity is achieved by shifting the emphasis from a direct assessment of the degree of damage to an expert assessment of the influencing objective factors, the assessment of which can be made with fewer errors with subsequent processing of the results by special mathematical methods.