The article shows the problems of old age security that has emerged in the last several years in connection with the changing conditions of the population and the economy's development. The quickly changing character of the pre-productive population is discussed in terms of the pension system's outlook. One change seen in recent years is the beginning of a decline in population, which is occurring despite the increasing life expectancy. In the future this drop will be reinforced by a declining marriage rate and a rising divorce rate. The Czech Republic has one of the lowest birth rates in Europe. If the funds allotted to social security do not increase, the average pension will decline as the number of old pensioners increases. Aside from the necessary raising of the retirement age, the basic way of developing security for old age will be to increase productivity. It is not realistic to count on increased employment to affect pension growth; the main source must be increased productivity. As the new system (with finances for old age security), which involves a more intensive exploitation of sources, gains importance, the "pay as you go" system will increase, too.