Equal professional opportunities with equal training? This is the central question, which the dissertation discusses. Often there are significant differences between the contents and the qualification levels of one's trained and practised profession. This study is based on the survey of gainfully employed persons in 2006. The author explores the reasons and factors leading to the changes of professions for men and women. The author scrutinises the questions how often gainfully employed persons are employed below their qualification levels and how this impacts incomes.