In view of these changes, it is useful to investigate whether the division of the labour market into formal and informal sectors gives rise to distinctive motherhood penalties. This is done by examining formal- and informal-sector wages for mothers and non-mothers in Argentina between 1995 and 2003, a period that spans the main liberalization policies set in motion in the early 1990s (Pastor and Wise, 1999). Our hypothesis is that the answers to all the above questions are affirmative because of the ways in which segmented labour markets differentially protect mothers working in the formal and informal sectors.