The multitude and complexity of factors determining career decisions result in the complexity of career decision process and the dynamics of inherent characteristics with reference to both individuals and social groups, for instance, generations. During the recent decade the representatives of Generation Y have entered the labour market; their values and behaviour differ from those characteristic of the representatives of Generation X who still prevail in the labour market. The emerging intergenerational conflict complicates the labour relations. Therefore, it is important to understand the reasons behind the career choice made by representatives of different generations. What has determined their career choice? How the dynamics of factors determining career decisions is related to the characteristics of different generations highlighted in the generational theory and the relevant historical and cultural context? The aim of the article is to reveal the Dynamics of factors that have determined the career decisions of Generations X and Y and to reveal similarities and differences.