Over the last few decades, family formation patterns have changed considerably. Increasing numbers of couples are cohabiting, although the majority still eventually marry. A study conducted by the Australian Institute of Family Studies highlights the changing trends in relationship formation and subsequent pathways. Based on data from the Australian Life Course Study, this article focuses on the first unions of women born in different years. It looks at how the first union of these women started (whether it began with cohabitation or marriage) and how old they were when they entered their first union. The proportions of women born in different years who had a child within four years of the start of their first union are also examined.