The article aims at revealing the importance of career designing for successful functioning of national qualification system, elaborating on historical development of career designing phenomenon and cultural change in various epochs. Premises underlying career designing philosophy are articulated and the main career designing philosophical category – vocation – is analysed in more detail, discussing its conception and importance in human life, including criteria for its manifestation. The relationship between aptitude and ability is analysed, differences between the concepts of intellect and intelligence are elucidated, taking into consideration the impact of phenomenological philosophy upon career designing methodology. A critical attitude to fallacious IQ (Intelligence quotient) concept treatment is presented. Ways of determining aptitude are discussed, the concept of core and special skills and their importance for career designing methodology is elucidated, and the most important principles underlying career designing are articulated.