The article has made an attempt to identify the ways in which adolescents and adults see the process of 'transitioning into adulthood' and what attributes they think are necessary for an adult person to possess. The problem of 'becoming an adult' has been portrayed in the broader context of parent-adolescent relation development. Research by Smetana (1988) has cast some light on a possible source of the conflict: differences in understanding social situations and the role of authority figures by adolescents and their parents. In contemporary society there are no unquestionable determinants of adulthood, a fact very conducive to intergenerational conflict. In the current study two groups of adolescents (15- and 18-year-olds) and a group of adults (38 to 56-year-olds) were examined using a questionnaire by J. J. Arnett (1997) The Attributes of Adulthood. The results show marked uniformity among subjects as to the choice of 'adulthood' characteristics. They point to events such as reaching a certain age, completing one's education or starting a family as the least important in transitioning to adolescence. The most popular categories, regardless of age, included subjective and psychological characteristics, such as financial independence, the ability to accept and fulfil new social roles or accepting responsibility for the consequences of one's actions. Reference to such ambiguous attributes can lead to parents and adolescents interpreting them differently and thus contribute to misunderstanding and conflict in parent-child relations.