This chapter focuses on the concept of integration, which is used in everyday political and academic discussions and has its opponents and defenders. The aim is to explore how it is defined, described and used in studies focusing on skilled immigrants’ integration into the workplace. The chapter is inspired by conceptual analysis and uses conceptual approaches such as everyday, scientific, formal and functional concepts to reflect on the results of the analysis. The results show that integration is not clearly defined in the studies, but assumed that readers know what is meant by it. The process nature of integration is highlighted in the studies, and its many uses such as integration to work community, vocational practices and society. It is concluded that researchers need to be more conscious of their use of the concept of integration and be transparent what do they mean by it.