The aging of population is one of the most significant determinants of world’s future development. Namely, it carries significant political, social and economic consequences, and as such it becomes the topic of distinct significance in the context of sociological, psychological, demographical and economical discussions. Aging cannot be observed as uniform process, but as an individual experience defined by biological, psychological and social factors. Croatia strives to follow European trends, and argues in favor of active, healthy and productive aging, which would secure equality within the society for the elderly, as well as prevent the emergence of age discrimination that represents serious social problem and affects the quality of life. Retirement represents an important transitional period in the life of an individual, and builds a strong basis for the development of different theories. The most notable ones are modernizational, functionalistic and systematic theory, but also the theory of exchange, roles and continuity. Retirement is greatly specified with the organization of retirement system of a country. Retirement system strives to protect individuals from the risks of aging, invalidity, etc. It can be conceived in a variety of ways, and Republic of Croatia brought in a three-part public-private retirement system in 2002, by introducing retirement reforms from 1999. The first pillar is a mandatory public retirement insurance based on intergenerational solidarity, while the second and third pillar represent a form of capital private insurance. Due to demographically unfavorable indicators, the burden of responsibility for security in the old age will be transferred from the state onto the individual exactly with the third retirement pillar, i.e. private capital insurance.