The GENPARENT project critically assesses theories on the transition to parenthood by comparing the division of work and care and its career related consequences in heterosexual and same-sex couples. Based on large-scale quantitative data analyses as well as in-depth interviews, the project shed light on couples’ reasons and motives for their division of work and care. The project addresses these issues from an internationally comparative gender regime perspective by following couples’ transitions to parenthood in four Nordic countries and the Netherlands.