Unemployment is classified today as one of the main threats to society. The phenomenon affects the lives of individuals, the functioning of families and society and development of the state. It is often the source of other social problems such as poverty, violence, or social pathologies. The article presents the scale and nature of unemployment occurring after 1989 in Poland and in selected European Union countries, i.e. the Netherlands, Spain, Slovakia and Latvia. It attempts to show the characteristic trends of the phenomenon over a period of more than two decades. Examples from the European countries analysed show that the situation in the labour market and the approach to employment are radically different. Individual countries are characterised by very different unemployment rates, which reflect their different size, economic and demographic potential, or are associated with the tradition of employment. The existence of differences seems to be normal, but their scale may give rise to concern. A characteristic feature of unemployment in the period analysed is its regional diversity, both in Poland and in the whole of the European community. Important factors that determine the level of unemployment are age, sex, education and people’s qualifications. The effects of long-term unemployment are very painful for the whole of society. Such a situation can lead to, amongst others, poverty, societal antagonism, violence and migration. The latter is an issue that the whole of Europe is currently struggling with. The uncontrolled influx of immigrants, including those migrating for economic reasons, causes fear of losing their job among Europeans, which in turn translates into the radicalisation of society. A role of the state and the EU institutions is to create an effective mechanism for the protection and support of the unemployed. This is a prerequisite for Europeans to continue the project which is a common united Europe.