This article provides an introduction to a special collection on childbearing among the descendants of immigrants in Europe. We will first review recent life-course research on fertility of immigrants and their descendants; we will then summarise the papers of this special issue; and finally we will discuss their contribution and future research avenues. The studies show significant heterogeneity in childbearing patterns among descendants of immigrants. Some groups have fertility levels similar to those of natives, some have lower fertility and some exhibit significantly higher fertility. Further, polarisation is characteristic to many descendant groups; some individuals have small families or even remain childless, whereas others have large families. We conclude that factors related to the mainstream society, minority subculture and minority status all shape fertility behaviour of immigrant descendants and that their impact varies across descendant groups. Future research should investigate whether the observed heterogeneity is likely to decline over generations or the diversity is here to stay for the long run.