Getty ImagesThe National Party’s proposal to extend paid parental leave from 26 to 30 weeks has made the issue an early talking point in the election campaign. And while voters’ attention will likely focus on the financial impact of an extra four weeks of leave, the provision allowing parents to overlap paid leave may prove the more significant change in the longer term. However, we know fathers can be reluctant to take advantage of paid parental leave if they perceive doing so might affect their career prospects.So the broader challenge lies in encouraging more fathers to take their entitled leave, normalising men’s involvement in caregiving, and reducing the work stigma that can surround taking leave.Why overlapping leave mattersSince 2020, primary carers in New Zealand have been entitled to 26 weeks of paid parental leave. While some or all of this entitlement can be transferred to a partner, only one parent can receive paid parental leave payments at a time. Consequently, partners who want to spend time at home together during the early weeks often rely on annual leave, unpaid leave, employer-provided leave or additional unpaid parental leave provisions. Of course, any proposal to extend parental leave is welcome. Research has linked longer parental leave to stronger parent-infant bonding and improved maternal and paternal mental health.Beyond immediate family wellbeing, however, allowing parents to take paid leave simultaneously may prove particularly important for how caregiving responsibilities are shared. The early weeks following the arrival of a child are often when caregiving patterns begin to take shape. Allowing both parents to be at home together during this period may help establish more shared caregiving routines from the outset. This has important implications for women’s careers. When caregiving responsibilities are shared more evenly from the beginning, mothers are less likely to shoulder the bulk of unpaid care and domestic work alongside paid employment. By spreading caregiving responsibilities more evenly, greater paternal involvement may help reduce the career disadvantages often associated with motherhood and support greater gender equality in the workplace. Use it or lose itThere are also important implications for men’s careers. Fathers are more likely to take parental leave when it is paid. Unpaid leave can create a direct tension between caring for a new child and fulfilling what they see as their breadwinner role. Allowing parents to take paid parental leave simultaneously may help ease this burden. But financial support alone may not be enough. Research on what is often called “flexibility stigma” suggests employees who use family-friendly policies may worry about being viewed as less committed to their jobs. Fathers are generally more willing to take leave when they believe it won’t harm their career prospects. This highlights where the policy challenge lies: designing parental leave policies that encourage – or even compel – fathers to use it.If the goal of parental leave policy is not just financial relief, but genuine gender equality in both paid work and caregiving, New Zealand will eventually need to look at how leave is allocated.Sweden provides an interesting example. Its parental leave system includes a non-transferable portion reserved for each parent on a “use it or lose it” basis. The aim is to encourage fathers to take leave and become active caregivers from the outset, helping to normalise caregiving as a shared responsibility. In fact, many OECD countries now provide some form of dedicated paid leave for fathers or non-primary caregivers, although entitlements differ markedly between countries. Reshaping workplacesReserving some leave for the non-primary caregiver has been associated with greater paternal involvement, a more equal sharing of unpaid work, and a reduction in the extent to which caregiving interrupts women’s careers. When taking parental leave becomes a normal part of working life for fathers, caregiving is less likely to be seen as incompatible with career commitment. That helps reshape both workplace and family practices.Allowing parents to take paid parental leave simultaneously has the potential to support family wellbeing, encourage fathers’ participation in care and reduce some of the barriers that continue to shape gendered divisions of labour. But international evidence suggests the debate may eventually need to move beyond how much leave parents receive and focus more closely on how leave is allocated and used. The current proposal may be an important step in that direction, but it is unlikely to be the end of the conversation.Joanne Mutter does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.